Elevator rope slip detector and elevator system

ABSTRACT

In an elevator apparatus, a pulley is provided in a hoistway. A rope that moves together with the movement of a car is wound around the pulley. Further, the pulley is provided with a pulley sensor for generating a signal according to the rotation of the pulley. The car is provided with a car speed sensor for directly detecting the speed of the car. A control panel is provided with: a first speed detecting portion for obtaining the speed of the car based on information from the pulley sensor; a second car speed detecting portion for obtaining the speed of the car based on information from the car speed sensor; and a determination portion for determining the presence/absence of slippage between the rope and the pulley by comparing the speeds of the car as respectively obtained by the first and second speed detecting portions.

TECHNICAL FIELD

The present invention relates to an elevator rope slippage detectingdevice for detecting the presence/absence of slippage of a rope, whichmoves in accordance with the movement of an elevator car, with respectto a pulley, and to an elevator apparatus using the elevator ropeslippage detecting device.

BACKGROUND ART

JP 2003-81549 A discloses an elevator car position detecting devicewhich, for detecting the position of a car within a hoistway, detectsthe position of the car by measuring the RPM of a pulley around which asteel tape that moves together with the car is wound. The pulley isprovided with a rotary encoder that outputs the RPM of the pulley in theform of a pulse signal. The pulse signal from the rotary encoder isinputted to a position determining portion. The position determiningportion determines the position of the car based on the input of thepulse signal.

In the elevator car position detecting device as described above,however, once slippage occurs between the rope and the pulley, therotation amount of the pulley no longer coincides with the traveldistance of the car, so a deviation occurs between the car position asdetermined by the position determining portion and the actual carposition. As a result, the operation of an elevator is controlled on thebasis of an erroneous car position that is different from the actual carposition, so there is a fear of the car coming into collision with thelower end portion of the hoistway.

DISCLOSURE OF THE INVENTION

The present invention has been made with a view to solving theabove-mentioned problem, and therefore it is an object of the presentinvention to provide an elevator rope slippage detecting device capableof detecting the presence/absence of slippage of a rope with respect toa pulley.

An elevator rope slippage detecting device according to the presentinvention relates to an elevator rope slippage detecting device fordetecting presence/absence of slippage between a rope that movestogether with a car traveling in a hoistway, and a pulley around whichthe rope is wound and which is rotated through movement of the rope,including: a pulley sensor for generating a signal in accordance withrotation of the pulley; a car speed sensor for directly detecting aspeed of the car; and a processing device having: a first speeddetecting portion for obtaining a speed of the car based on informationfrom the pulley sensor; a second car speed detecting portion forobtaining a speed of the car based on information from the car speedsensor; and a determination portion for determining the presence/absenceof slippage between the rope and the pulley by comparing the speed ofthe car obtained by the first speed detecting portion and the speed ofthe car obtained by the second speed detecting portion with each other.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram showing an elevator apparatus according toEmbodiment 1 of the present invention.

FIG. 2 is a front view showing the safety device of FIG. 1.

FIG. 3 is a front view showing the safety device of FIG. 2 that has beenactuated.

FIG. 4 is a schematic diagram showing an elevator apparatus according toEmbodiment 2 of the present invention.

FIG. 5 is a front view showing the safety device of FIG. 4.

FIG. 6 is a front view showing the safety device of FIG. 5 that has beenactuated.

FIG. 7 is a front view showing the drive portion of FIG. 6.

FIG. 8 is a schematic diagram showing an elevator apparatus according toEmbodiment 3 of the present invention.

FIG. 9 is a schematic diagram showing an elevator apparatus according toEmbodiment 4 of the present invention.

FIG. 10 is a schematic diagram showing an elevator apparatus accordingto Embodiment 5 of the present invention.

FIG. 11 is a schematic diagram showing an elevator apparatus accordingto Embodiment 6 of the present invention.

FIG. 12 is a schematic diagram showing another example of the elevatorapparatus shown in FIG. 11.

FIG. 13 is a schematic diagram showing an elevator apparatus accordingto Embodiment 7 of the present invention.

FIG. 14 is a schematic diagram showing an elevator apparatus accordingto Embodiment 8 of the present invention.

FIG. 15 is a front view showing another example of the drive portionshown in FIG. 7.

FIG. 16 is a plan view showing a safety device according to Embodiment 9of the present invention.

FIG. 17 is a partially cutaway side view showing a safety deviceaccording to Embodiment 10 of the present invention.

FIG. 18 is a schematic diagram showing an elevator apparatus accordingto Embodiment 11 of the present invention.

FIG. 19 is a graph showing the car speed abnormality determinationcriteria stored in the memory portion of FIG. 18.

FIG. 20 is a graph showing the car acceleration abnormalitydetermination criteria stored in the memory portion of FIG. 18.

FIG. 21 is a schematic diagram showing an elevator apparatus accordingto Embodiment 12 of the present invention.

FIG. 22 is a schematic diagram showing an elevator apparatus accordingto Embodiment 13 of the present invention.

FIG. 23 is a diagram showing the rope fastening device and the ropesensors of FIG. 22.

FIG. 24 is a diagram showing a state where one of the main ropes of FIG.23 has broken.

FIG. 25 is a schematic diagram showing an elevator apparatus accordingto Embodiment 14 of the present invention.

FIG. 26 is a schematic diagram showing an elevator apparatus accordingto Embodiment 15 of the present invention.

FIG. 27 is a perspective view of the car and the door sensor of FIG. 26.

FIG. 28 is a perspective view showing a state in which the car entrance26 of FIG. 27 is open.

FIG. 29 is a schematic diagram showing an elevator apparatus accordingto Embodiment 16 of the present invention.

FIG. 30 is a diagram showing an upper portion of the hoistway of FIG.29.

FIG. 31 is a schematic diagram showing an elevator apparatus accordingto Embodiment 17 of the present invention.

FIG. 32 is a schematic diagram showing an elevator apparatus accordingto Embodiment 18 of the present invention.

FIG. 33 is a schematic diagram showing an elevator apparatus accordingto Embodiment 19 of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinbelow, preferred embodiments of the present invention aredescribed with reference to the drawings.

Embodiment 1

FIG. 1 is a schematic diagram showing an elevator apparatus according toEmbodiment 1 of the present invention. Referring to FIG. 1, a pair ofcar guide rails 2 are arranged within a hoistway 1. A car 3 is guided bythe car guide rails 2 as it is raised and lowered in the hoistway 1.Arranged at the upper end portion of the hoistway 1 is a hoistingmachine (not shown) for raising and lowering the car 3 and acounterweight (not shown). A main rope 4 is wound around a drivingsheave of the hoisting machine. The car 3 and the counterweight aresuspended in the hoistway 1 by means of the main rope 4. Mounted to thecar 3 are a pair of safety devices 5 opposed to the respective guiderails 2 and serving as braking means. The safety devices 5 are arrangedon the underside of the car 3. Braking is applied to the car 3 uponactuating the safety devices 5.

Also arranged at the upper end portion of the hoistway 1 is a governor 6serving as a car speed detecting means for detecting theascending/descending speed of the car 3. The governor 6 has a governormain body 7 and a governor sheave 8 rotatable with respect to thegovernor main body 7. A rotatable tension pulley 9 is arranged at alower end portion of the hoistway 1. Wound between the governor sheave 8and the tension pulley 9 is a governor rope 10 connected to the car 3.The connecting portion between the governor rope 10 and the car 3undergoes vertical reciprocating motion as the car 3 travels. As aresult, the governor sheave 8 and the tension pulley 9 are rotated at aspeed corresponding to the ascending/descending speed of the car 3.

The governor 6 is adapted to actuate a braking device of the hoistingmachine when the ascending/descending speed of the car 3 has reached apreset first overspeed. Further, the governor 6 is provided with aswitch portion 11 serving as an output portion through which anactuation signal is output to the safety devices 5 when the descendingspeed of the car 3 reaches a second overspeed (set overspeed) higherthan the first overspeed. The switch portion 11 has a contact 16 whichis mechanically opened and closed by means of an overspeed lever that isdisplaced according to the centrifugal force of the rotating governorsheave 8. The contact 16 is electrically connected to a battery 12,which is an uninterruptible power supply capable of feeding power evenin the event of a power failure, and to a control panel 13 that controlsthe drive of an elevator, through a power supply cable 14 and aconnection cable 15, respectively.

A control cable (movable cable) is connected between the car 3 and thecontrol panel 13. The control cable includes, in addition to multiplepower lines and signal lines, an emergency stop wiring 17 electricallyconnected between the control panel 13 and each safety device 5. Byclosing of the contact 16, power from the battery 12 is supplied to eachsafety device 5 by way of the power supply cable 14, the switch portion11, the connection cable 15, a power supply circuit within the controlpanel 13, and the emergency stop wiring 17. It should be noted thattransmission means consists of the connection cable 15, the power supplycircuit within the control panel 13, and the emergency stop wiring 17.

FIG. 2 is a front view showing the safety device 5 of FIG. 1, and FIG. 3is a front view showing the safety device 5 of FIG. 2 that has beenactuated. Referring to the figures, a support member 18 is fixed inposition below the car 3. The safety device 5 is fixed to the supportmember 18. Further, each safety device 5 includes a pair of actuatorportions 20, which are connected to a pair of wedges 19 serving asbraking members and capable of moving into and away from contact withthe car guide rail 2 to displace the wedges 19 with respect to the car3, and a pair of guide portions 21 which are fixed to the support member18 and guide the wedges 19 displaced by the actuator portions 20 intocontact with the car guide rail 2. The pair of wedges 19, the pair ofactuator portions 20, and the pair of guide portions 21 are eacharranged symmetrically on both sides of the car guide rail 2.

Each guide portion 21 has an inclined surface 22 inclined with respectto the car guide rail 2 such that the distance between it and the carguide rail 2 decreases with increasing proximity to its upper portion.The wedge 19 is displaced along the inclined surface 22. Each actuatorportion 20 includes a spring 23 serving as an urging portion that urgesthe wedge 19 upward toward the guide portion 21 side, and anelectromagnet 24 which, when supplied with electric current, generatesan electromagnetic force for displacing the wedge 19 downward away fromthe guide member 21 against the urging force of the spring 23.

The spring 23 is connected between the support member 18 and the wedge19. The electromagnet 24 is fixed to the support member 18. Theemergency stop wiring 17 is connected to the electromagnet 24. Fixed toeach wedge 19 is a permanent magnet 25 opposed to the electromagnet 24.The supply of electric current to the electromagnet 24 is performed fromthe battery 12 (see FIG. 1) by the closing of the contact 16 (see FIG.1). The safety device 5 is actuated as the supply of electric current tothe electromagnet 24 is cut off by the opening of the contact 16 (seeFIG. 1). That is, the pair of wedges 19 are displaced upward due to theelastic restoring force of the spring 23 to be pressed against the carguide rail 2.

Next, operation is described. The contact 16 remains closed duringnormal operation. Accordingly, power is supplied from the battery 12 tothe electromagnet 24. The wedge 19 is attracted and held on to theelectromagnet 24 by the electromagnetic force generated upon this powersupply, and thus remains separated from the car guide rail 2 (FIG. 2).

When, for instance, the speed of the car 3 rises to reach the firstoverspeed due to a break in the main rope 4 or the like, this actuatesthe braking device of the hoisting machine. When the speed of the car 3rises further even after the actuation of the braking device of thehoisting machine and reaches the second overspeed, this triggers closureof the contact 16. As a result, the supply of electric current to theelectromagnet 24 of each safety device 5 is cut off, and the wedges 19are displaced by the urging force of the springs 23 upward with respectto the car 3. At this time, the wedges 19 are displaced along theinclined surface 22 while in contact with the inclined surface 22 of theguide portions 21. Due to this displacement, the wedges 19 are pressedinto contact with the car guide rail 2. The wedges 19 are displacedfurther upward as they come into contact with the car guide rail 2, tobecome wedged in between the car guide rail 2 and the guide portions 21.A large frictional force is thus generated between the car guide rail 2and the wedges 19, braking the car 3 (FIG. 3).

To release the braking on the car 3, the car 3 is raised while supplyingelectric current to the electromagnet 24 by the closing of the contact16. As a result, the wedges 19 are displaced downward, thus separatingfrom the car guide rail 2.

In the above-described elevator apparatus, the switch portion 11connected to the battery 12 and each safety device 5 are electricallyconnected to each other, whereby an abnormality in the speed of the car3 detected by the governor 6 can be transmitted as an electricalactuation signal from the switch portion 11 to each safety device 5,making it possible to brake the car 3 in a short time after detecting anabnormality in the speed of the car 3. As a result, the braking distanceof the car 3 can be reduced. Further, synchronized actuation of therespective safety devices 5 can be readily effected, making it possibleto stop the car 3 in a stable manner. Also, each safety device 5 isactuated by the electrical actuation signal, thus preventing the safetydevice 5 from being erroneously actuated due to shaking of the car 3 orthe like.

Additionally, each safety device 5 has the actuator portions 20 whichdisplace the wedge 19 upward toward the guide portion 21 side, and theguide portions 21 each including the inclined surface 22 to guide theupwardly displaced wedge 19 into contact with the car guide rail 2,whereby the force with which the wedge 19 is pressed against the carguide rail 2 during descending movement of the car 3 can be increasedwith reliability.

Further, each actuator portion 20 has a spring 23 that urges the wedge19 upward, and an electromagnet 24 for displacing the wedge 19 downwardagainst the urging force of the spring 23, thereby enabling displacementof the wedge 19 by means of a simple construction.

Embodiment 2

FIG. 4 is a schematic diagram showing an elevator apparatus according toEmbodiment 2 of the present invention. Referring to FIG. 4, the car 3has a car main body 27 provided with a car entrance 26, and a car door28 that opens and closes the car entrance 26. Provided in the hoistway 1is a car speed sensor 31 serving as car speed detecting means fordetecting the speed of the car 3. Mounted inside the control panel 13 isan output portion 32 electrically connected to the car speed sensor 31.The battery 12 is connected to the output portion 32 through the powersupply cable 14. Electric power used for detecting the speed of the car3 is supplied from the output portion 32 to the car speed sensor 31. Theoutput portion 32 is input with a speed detection signal from the carspeed sensor 31.

Mounted on the underside of the car 3 are a pair of safety devices 33serving as braking means for braking the car 3. The output portion 32and each safety device 33 are electrically connected to each otherthrough the emergency stop wiring 17. When the speed of the car 3 is atthe second overspeed, an actuation signal, which is the actuating power,is output to each safety device 33. The safety devices 33 are actuatedupon input of this actuation signal.

FIG. 5 is a front view showing the safety device 33 of FIG. 4, and FIG.6 is a front view showing the safety device 33 of FIG. 5 that has beenactuated. Referring to the figures, the safety device 33 has a wedge 34serving as a braking member and capable of moving into and away fromcontact with the car guide rail 2, an actuator portion 35 connected to alower portion of the wedge 34, and a guide portion 36 arranged above thewedge 34 and fixed to the car 3. The wedge 34 and the actuator portion35 are capable of vertical movement with respect to the guide portion36. As the wedge 34 is displaced upward with respect to the guideportion 36, that is, toward the guide portion 36 side, the wedge 34 isguided by the guide portion 36 into contact with the car guide rail 2.

The actuator portion 35 has a cylindrical contact portion 37 capable ofmoving into and away from contact with the car guide rail 2, anactuating mechanism 38 for displacing the contact portion 37 into andaway from contact with the car guide rail 2, and a support portion 39supporting the contact portion 37 and the actuating mechanism 38. Thecontact portion 37 is lighter than the wedge 34 so that it can bereadily displaced by the actuating mechanism 38. The actuating mechanism38 has a movable portion 40 capable of reciprocating displacementbetween a contact position where the contact portion 37 is held incontact with the car guide rail 2 and a separated position where thecontact portion 37 is separated from the car guide rail 2, and a driveportion 41 for displacing the movable portion 40.

The support portion 39 and the movable portion 40 are provided with asupport guide hole 42 and a movable guide hole 43, respectively. Theinclination angles of the support guide hole 42 and the movable guidehole 43 with respect to the car guide rail 2 are different from eachother. The contact portion 37 is slidably fitted in the support guidehole 42 and the movable guide hole 43. The contact portion 37 slideswithin the movable guide hole 43 according to the reciprocatingdisplacement of the movable portion 40, and is displaced along thelongitudinal direction of the support guide hole 42. As a result, thecontact portion 37 is moved into and away from contact with the carguide rail 2 at an appropriate angle. When the contact portion 37 comesinto contact with the car guide rail 2 as the car 3 descends, braking isapplied to the wedge 34 and the actuator portion 35, displacing themtoward the guide portion 36 side.

Mounted on the upperside of the support portion 39 is a horizontal guidehole 47 extending in the horizontal direction. The wedge 34 is slidablyfitted in the horizontal guide hole 47. That is, the wedge 34 is capableof reciprocating displacement in the horizontal direction with respectto the support portion 39.

The guide portion 36 has an inclined surface 44 and a contact surface 45which are arranged so as to sandwich the car guide rail 2 therebetween.The inclined surface 44 is inclined with respect to the car guide rail 2such that the distance between it and the car guide rail 2 decreaseswith increasing proximity to its upper portion. The contact surface 45is capable of moving into and away from contact with the car guide rail2. As the wedge 34 and the actuator portion 35 are displaced upward withrespect to the guide portion 36, the wedge 34 is displaced along theinclined surface 44. As a result, the wedge 34 and the contact surface45 are displaced so as to approach each other, and the car guide rail 2becomes lodged between the wedge 34 and the contact surface 45.

FIG. 7 is a front view showing the drive portion 41 of FIG. 6. Referringto FIG. 7, the drive portion 41 has a disc spring 46 serving as anurging portion and attached to the movable portion 40, and anelectromagnet 48 for displacing the movable portion 40 by anelectromagnetic force generated upon supply of electric current thereto.

The movable portion 40 is fixed to the central portion of the discspring 46. The disc spring 46 is deformed due to the reciprocatingdisplacement of the movable portion 40. As the disc spring 46 isdeformed due to the displacement of the movable portion 40, the urgingdirection of the disc spring 46 is reversed between the contact position(solid line) and the separated position (broken line). The movableportion 40 is retained at the contact or separated position as it isurged by the disc spring 46. That is, the contact or separated state ofthe contact portion 37 with respect to the car guide rail 2 is retainedby the urging of the disc spring 46.

The electromagnet 48 has a first electromagnetic portion 49 fixed to themovable portion 40, and a second electromagnetic portion 50 opposed tothe first electromagnetic portion 49. The movable portion 40 isdisplaceable relative to the second electromagnetic portion 50. Theemergency stop wiring 17 is connected to the electromagnet 48. Uponinputting an actuation signal to the electromagnet 48, the firstelectromagnetic portion 49 and the second electromagnetic portion 50generate electromagnetic forces so as to repel each other. That is, uponinput of the actuation signal to the electromagnet 48, the firstelectromagnetic portion 49 is displaced away from contact with thesecond electromagnetic portion 50, together with the movable portion 40.

It should be noted that for recovery after the actuation of the safetydevice 5, the output portion 32 outputs a recovery signal during therecovery phase. Input of the recovery signal to the electromagnet 48causes the first electromagnetic portion 49 and the secondelectromagnetic portion 50 to attract each other. Otherwise, thisembodiment is of the same construction as Embodiment 1.

Next, operation is described. During normal operation, the movableportion 40 is located at the separated position, and the contact portion37 is urged by the disc spring 46 to be separated away from contact withthe car guide rail 2. With the contact portion 37 thus being separatedfrom the car guide rail 2, the wedge 34 is separated from the guideportion 36, thus maintaining the distance between the wedge 34 and theguide portion 36.

When the speed detected by the car speed sensor 31 reaches the firstoverspeed, this actuates the braking device of the hoisting machine.When the speed of the car 3 continues to rise thereafter and the speedas detected by the car speed sensor 31 reaches the second overspeed, anactuation signal is output from the output portion 32 to each safetydevice 33. In putting this actuation signal to the electromagnet 48triggers the first electromagnetic portion 49 and the secondelectromagnetic portion 50 to repel each other. The electromagneticrepulsion force thus generated causes the movable portion 40 to bedisplaced into the contact position. As this happens, the contactportion 37 is displaced into contact with the car guide rail 2. By thetime the movable portion 40 reaches the contact position, the urgingdirection of the disc spring 46 reverses to that for retaining themovable portion 40 at the contact position. As a result, the contactportion 37 is pressed into contact with the car guide rail 2, thusbraking the wedge 34 and the actuator portion 35.

Since the car 3 and the guide portion 36 descend with no braking appliedthereon, the guide portion 36 is displaced downward towards the wedge 34and actuator 35 side. Due to this displacement, the wedge 34 is guidedalong the inclined surface 44, causing the car guide rail 2 to becomelodged between the wedge 34 and the contact surface 45. As the wedge 34comes into contact with the car guide rail 2, it is displaced furtherupward to wedge in between the car guide rail 2 and the inclined surface44. A large frictional force is thus generated between the car guiderail 2 and the wedge 34, and between the car guide rail 2 and thecontact surface 45, thus braking the car 3.

During the recovery phase, the recovery signal is transmitted from theoutput portion 32 to the electromagnet 48. This causes the firstelectromagnetic portion 49 and the second electromagnetic portion 50 toattract each other, thus displacing the movable portion 40 to theseparated position. As this happens, the contact portion 37 is displacedto be separated away from contact with the car guide rail 2. By the timethe movable portion 40 reaches the separated position, the urgingdirection of the disc spring 46 reverses, allowing the movable portion40 to be retained at the separated position. As the car 3 ascends inthis state, the pressing contact of the wedge 34 and the contact surface45 with the car guide rail 2 is released.

In addition to providing the same effects as those of Embodiment 1, theabove-described elevator apparatus includes the car speed sensor 31provided in the hoistway 1 to detect the speed of the car 3. There isthereby no need to use a speed governor and a governor rope, making itpossible to reduce the overall installation space for the elevatorapparatus.

Further, the actuator portion 35 has the contact portion 37 capable ofmoving into and away from contact with the car guide rail 2, and theactuating mechanism 38 for displacing the contact portion 37 into andaway from contact with the car guide rail 2. Accordingly, by making theweight of the contact portion 37 smaller than that of the wedge 34, thedrive force to be applied from the actuating mechanism 38 to the contactportion 37 can be reduced, thus making it possible to miniaturize theactuating mechanism 38. Further, the lightweight construction of thecontact portion 37 allows increases in the displacement rate of thecontact portion 37, thereby reducing the time required until generationof a braking force.

Further, the drive portion 41 includes the disc spring 46 adapted tohold the movable portion 40 at the contact position or the separatedposition, and the electromagnet 48 capable of displacing the movableportion 40 when supplied with electric current, whereby the movableportion 40 can be reliably held at the contact or separated position bysupplying electric current to the electromagnet 48 only during thedisplacement of the movable portion 40.

Embodiment 3

FIG. 8 is a schematic diagram showing an elevator apparatus according toEmbodiment 3 of the present invention. Referring to FIG. 8, provided atthe car entrance 26 is a door closed sensor 58, which serves as a doorclosed detecting means for detecting the open or closed state of the cardoor 28. An output portion 59 mounted on the control panel 13 isconnected to the door closed sensor 58 through a control cable. Further,the car speed sensor 31 is electrically connected to the output portion59. A speed detection signal from the car speed sensor 31 and anopen/closed detection signal from the door closed sensor 58 are input tothe output portion 59. On the basis of the speed detection signal andthe open/closed detection signal thus input, the output portion 59 candetermine the speed of the car 3 and the open or closed state of the carentrance 26.

The output portion 59 is connected to each safety device 33 through theemergency stop wiring 17. On the basis of the speed detection signalfrom the car speed sensor 31 and the opening/closing detection signalfrom the door closed sensor 58, the output portion 59 outputs anactuation signal when the car 3 has descended with the car entrance 26being open. The actuation signal is transmitted to the safety device 33through the emergency stop wiring 17. Otherwise, this embodiment is ofthe same construction as Embodiment 2.

In the elevator apparatus as described above, the car speed sensor 31that detects the speed of the car 3, and the door closed sensor 58 thatdetects the open or closed state of the car door 28 are electricallyconnected to the output portion 59, and the actuation signal is outputfrom the output portion 59 to the safety device 33 when the car 3 hasdescended with the car entrance 26 being open, thereby preventing thecar 3 from descending with the car entrance 26 being open.

It should be noted that safety devices vertically reversed from thesafety devices 33 may be mounted to the car 3. This construction alsomakes it possible to prevent the car 3 from ascending with the carentrance 26 being open.

Embodiment 4

FIG. 9 is a schematic diagram showing an elevator apparatus according toEmbodiment 4 of the present invention. Referring to FIG. 9, passedthrough the main rope 4 is a break detection lead wire 61 serving as arope break detecting means for detecting a break in the rope 4. A weakcurrent flows through the break detection lead wire 61. The presence ofa break in the main rope 4 is detected on the basis of the presence orabsence of this weak electric current passing therethough. An outputportion 62 mounted on the control panel 13 is electrically connected tothe break detection lead wire 61. When the break detection lead wire 61breaks, a rope break signal, which is an electric current cut-off signalof the break detection lead wire 61, is input to the output portion 62.The car speed sensor 31 is also electrically connected to the outputportion 62.

The output portion 62 is connected to each safety device 33 through theemergency stop wiring 17. If the main rope 4 breaks, the output portion62 outputs an actuation signal on the basis of the speed detectionsignal from the car speed sensor 31 and the rope break signal from thebreak detection lead wire 61. The actuation signal is transmitted to thesafety device 33 through the emergency stop wiring 17. Otherwise, thisembodiment is of the same construction as Embodiment 2.

In the elevator apparatus as described above, the car speed sensor 31which detects the speed of the car 3 and the break detection lead wire61 which detects a break in the main rope 4 are electrically connectedto the output portion 62, and, when the main rope 4 breaks, theactuation signal is output from the output portion 62 to the safetydevice 33. By thus detecting the speed of the car 3 and detecting abreak in the main rope 4, braking can be more reliably applied to a car3 that is descending at abnormal speed.

While in the above example the method of detecting the presence orabsence of an electric current passing through the break detection leadwire 61, which is passed through the main rope 4, is employed as therope break detecting means, it is also possible to employ a method of,for example, measuring changes in the tension of the main rope 4. Inthis case, a tension measuring instrument is installed on the ropefastening.

Embodiment 5

FIG. 10 is a schematic diagram showing an elevator apparatus accordingto Embodiment 5 of the present invention. Referring to FIG. 10, providedin the hoistway 1 is a car position sensor 65 serving as car positiondetecting means for detecting the position of the car 3. The carposition sensor 65 and the car speed sensor 31 are electricallyconnected to an output portion 66 mounted on the control panel 13. Theoutput portion 66 has a memory portion 67 storing a control patterncontaining information on the position, speed,acceleration/deceleration, floor stops, etc., of the car 3 during normaloperation. Inputs to the output portion 66 are a speed detection signalfrom the car speed sensor 31 and a car position signal from the carposition sensor 65.

The output portion 66 is connected to the safety device 33 through theemergency stop wiring 17. The output portion 66 compares the speed andposition (actual measured values) of the car 3 based on the speeddetection signal and the car position signal with the speed and position(set values) of the car 3 based on the control pattern stored in thememory portion 67. The output portion 66 outputs an actuation signal tothe safety device 33 when the deviation between the actual measuredvalues and the set values exceeds a predetermined threshold. Herein, thepredetermined threshold refers to the minimum deviation between theactual measurement values and the set values required for bringing thecar 3 to a halt through normal braking without the car 3 collidingagainst an end portion of the hoistway 1. Otherwise, this embodiment isof the same construction as Embodiment 2.

In the elevator apparatus as described above, the output portion 66outputs the actuation signal when the deviation between the actualmeasurement values from each of the car speed sensor 31 and the carposition sensor 65 and the set values based on the control patternexceeds the predetermined threshold, making it possible to preventcollision of the car 3 against the end portion of the hoistway 1.

Embodiment 6

FIG. 11 is a schematic diagram showing an elevator apparatus accordingto Embodiment 6 of the present invention. Referring to FIG. 11, arrangedwithin the hoistway 1 are an upper car 71 that is a first car and alower car 72 that is a second car located below the upper car 71. Theupper car 71 and the lower car 72 are guided by the car guide rail 2 asthey ascend and descend in the hoistway 1. Installed at the upper endportion of the hoistway 1 are a first hoisting machine (not shown) forraising and lowering the upper car 71 and an upper-car counterweight(not shown), and a second hoisting machine (not shown) for raising andlowering the lower car 72 and a lower-car counterweight (not shown). Afirst main rope (not shown) is wound around the driving sheave of thefirst hoisting machine, and a second main rope (not shown) is woundaround the driving sheave of the second hoisting machine. The upper car71 and the upper-car counterweight are suspended by the first main rope,and the lower car 72 and the lower-car counterweight are suspended bythe second main rope.

In the hoistway 1, there are provided an upper-car speed sensor 73 and alower-car speed sensor 74 respectively serving as car speed detectingmeans for detecting the speed of the upper car 71 and the speed of thelower car 72. Also provided in the hoistway 1 are an upper-car positionsensor 75 and a lower-car position sensor 76 respectively serving as carposition detecting means for detecting the position of the upper car 71and the position of the lower car 72.

It should be noted that car operation detecting means includes theupper-car speed sensor 73, the lower-car sped sensor 74, the upper-carposition sensor 75, and the lower-car position sensor 76.

Mounted on the underside of the upper car 71 are upper-car safetydevices 77 serving as braking means of the same construction as that ofthe safety devices 33 used in Embodiment 2. Mounted on the underside ofthe lower car 72 are lower-car safety devices 78 serving as brakingmeans of the same construction as that of the upper-car safety devices77.

An output portion 79 is mounted inside the control panel 13. Theupper-car speed sensor 73, the lower-car speed sensor 74, the upper-carposition sensor 75, and the lower-car position sensor 76 areelectrically connected to the output portion 79. Further, the battery 12is connected to the output portion 79 through the power supply cable 14.An upper-car speed detection signal from the upper-car speed sensor 73,a lower-car speed detection signal from the lower-car speed sensor 74,an upper-car position detecting signal from the upper-car positionsensor 75, and a lower-car position detection signal from the lower-carposition sensor 76 are input to the output portion 79. That is,information from the car operation detecting means is input to theoutput portion 79.

The output portion 79 is connected to the upper-car safety device 77 andthe lower-car safety device 78 through the emergency stop wiring 17.Further, on the basis of the information from the car operationdetecting means, the output portion 79 predicts whether or not the uppercar 71 or the lower car 72 will collide against an end portion of thehoistway 1 and whether or not collision will occur between the upper car71 and the lower car 72; when it is predicted that such collision willoccur, the output portion 79 outputs an actuation signal to each theupper-car safety devices 77 and the lower-car safety devices 78. Theupper-car safety devices 77 and the lower-car safety devices 78 are eachactuated upon input of this actuation signal.

It should be noted that a monitoring portion includes the car operationdetecting means and the output portion 79. The running states of theupper car 71 and the lower car 72 are monitored by the monitoringportion. Otherwise, this embodiment is of the same construction asEmbodiment 2.

Next, operation is described. When input with the information from thecar operation detecting means, the output portion 79 predicts whether ornot the upper car 71 and the lower car 72 will collide against an endportion of the hoistway 1 and whether or not collision between the uppercar and the lower car 72 will occur. For example, when the outputportion 79 predicts that collision will occur between the upper car 71and the lower car 72 due to a break in the first main rope suspendingthe upper car 71, the output portion 79 outputs an actuation signal toeach the upper-car safety devices 77 and the lower-car safety devices78. The upper-car safety devices 77 and the lower-car safety devices 78are thus actuated, braking the upper car 71 and the lower car 72.

In the elevator apparatus as described above, the monitoring portion hasthe car operation detecting means for detecting the actual movements ofthe upper car 71 and the lower car 72 as they ascend and descend in thesame hoistway 1, and the output portion 79 which predicts whether or notcollision will occur between the upper car 71 and the lower car 72 onthe basis of the information from the car operation detecting means and,when it is predicted that the collision will occur, outputs theactuation signal to each of the upper-car safety devices 77 and thelower-car emergency devices 78. Accordingly, even when the respectivespeeds of the upper car 71 and the lower car 72 have not reached the setoverspeed, the upper-car safety devices 77 and the lower-car emergencydevices 78 can be actuated when it is predicted that collision willoccur between the upper car 71 and the lower car 72, thereby making itpossible to avoid a collision between the upper car 71 and the lower car72.

Further, the car operation detecting means has the upper-car speedsensor 73, the lower-car speed sensor 74, the upper-car position sensor75, and the lower-car position sensor 76, the actual movements of theupper car 71 and the lower car 72 can be readily detected by means of asimple construction.

While in the above-described example the output portion 79 is mountedinside the control panel 13, an output portion 79 may be mounted on eachof the upper car 71 and the lower car 72. In this case, as shown in FIG.12, the upper-car speed sensor 73, the lower-car speed sensor 74, theupper-car position sensor 75, and the lower-car position sensor 76 areelectrically connected to each of the output portions 79 mounted on theupper car 71 and the lower car 72.

While in the above-described example the output portions 79 outputs theactuation signal to each the upper-car safety devices 77 and thelower-car safety devices 78, the output portion 79 may, in accordancewith the information from the car operation detecting means, output theactuation signal to only one of the upper-car safety device 77 and thelower-car safety device 78. In this case, in addition to predictingwhether or not collision will occur between the upper car 71 and thelower car 72, the output portions 79 also determine the presence of anabnormality in the respective movements of the upper car 71 and thelower car 72. The actuation signal is output from an output portion 79to only the safety device mounted on the car which is moving abnormally.

Embodiment 7

FIG. 13 is a schematic diagram showing an elevator apparatus accordingto Embodiment 7 of the present invention. Referring to FIG. 13, anupper-car output portion 81 serving as an output portion is mounted onthe upper car 71, and a lower-car output portion 82 serving as an outputportion is mounted on the lower car 72. The upper-car speed sensor 73,the upper-car position sensor 75, and the lower-car position sensor 76are electrically connected to the upper-car output portion 81. Thelower-car speed sensor 74, the lower-car position sensor 76, and theupper-car position sensor 75 are electrically connected to the lower-caroutput portion 82.

The upper-car output portion 81 is electrically connected to theupper-car safety devices 77 through an upper-car emergency stop wiring83 serving as transmission means installed on the upper car 71. Further,the upper-car output portion 81 predicts, on the basis of information(hereinafter referred to as “upper-car detection information” in thisembodiment) from the upper-car speed sensor 73, the upper-car positionsensor 75, and the lower-car position sensor 76, whether or not theupper car 71 will collide against the lower car 72, and outputs anactuation signal to the upper-car safety devices 77 upon predicting thata collision will occur. Further, when input with the upper-car detectioninformation, the upper-car output portion 81 predicts whether or not theupper car 71 will collide against the lower car 72 on the assumptionthat the lower car 72 is running toward the upper car 71 at its maximumnormal operation speed.

The lower-car output portion 82 is electrically connected to thelower-car safety devices 78 through a lower-car emergency stop wiring 84serving as transmission means installed on the lower car 72. Further,the lower-car output portion 82 predicts, on the basis of information(hereinafter referred to as “lower-car detection information” in thisembodiment) from the lower-car speed sensor 74, the lower-car positionsensor 76, and the upper-car position sensor 75, whether or not thelower car 72 will collide against the upper car 71, and outputs anactuation signal to the lower-car safety devices 78 upon predicting thata collision will occur. Further, when input with the lower-car detectioninformation, the lower-car output portion 82 predicts whether or not thelower car 72 will collide against the upper car 71 on the assumptionthat the upper car 71 is running toward the lower car 72 at its maximumnormal operation speed.

Normally, the operations of the upper car 71 and the lower car 72 arecontrolled such that they are sufficiently spaced away from each otherso that the upper-car safety devices 77 and the lower-car safety devices78 do not actuate. Otherwise, this embodiment is of the sameconstruction as Embodiment 6.

Next, operation is described. For instance, when, due to a break in thefirst main rope suspending the upper car 71, the upper car 71 fallstoward the lower car 72, the upper-car output portion 81 and thelower-car output portion 82 both predict the impending collision betweenthe upper car 71 and the lower car 72. As a result, the upper-car outputportion 81 and the lower-car output portion 82 each output an actuationsignal to the upper-car safety devices 77 and the lower-car safetydevices 78, respectively. This actuates the upper-car safety devices 77and the lower-car safety devices 78, thus braking the upper car 71 andthe lower car 72.

In addition to providing the same effects as those of Embodiment 6, theabove-described elevator apparatus, in which the upper-car speed sensor73 is electrically connected to only the upper-car output portion 81 andthe lower-car speed sensor 74 is electrically connected to only thelower-car output portion 82, obviates the need to provide electricalwiring between the upper-car speed sensor 73 and the lower-car outputportion 82 and between the lower-car speed sensor 74 and the upper-caroutput portion 81, making it possible to simplify the electrical wiringinstallation.

Embodiment 8

FIG. 14 is a schematic diagram showing an elevator apparatus accordingto Embodiment 8 of the present invention. Referring to FIG. 14, mountedto the upper car 71 and the lower car 72 is an inter-car distance sensor91 serving as inter-car distance detecting means for detecting thedistance between the upper car 71 and the lower car 72. The inter-cardistance sensor 91 includes a laser irradiation portion mounted on theupper car 71 and a reflection portion mounted on the lower car 72. Thedistance between the upper car 71 and the lower car 72 is obtained bythe inter-car distance sensor 91 based on the reciprocation time oflaser light between the laser irradiation portion and the reflectionportion.

The upper-car speed sensor 73, the lower-car speed sensor 74, theupper-car position sensor 75, and the inter-car distance sensor 91 areelectrically connected to the upper-car output portion 81. The upper-carspeed sensor 73, the lower-car speed sensor 74, the lower-car positionsensor 76, and the inter-car distance sensor 91 are electricallyconnected to the lower-car output portion 82.

The upper-car output portion 81 predicts, on the basis of information(hereinafter referred to as “upper-car detection information” in thisembodiment) from the upper-car speed sensor 73, the lower-car speedsensor 74, the upper-car position sensor 75, and the inter-car distancesensor 91, whether or not the upper car 71 will collide against thelower car 72, and outputs an actuation signal to the upper-car safetydevices 77 upon predicting that a collision will occur.

The lower-car output portion 82 predicts, on the basis of information(hereinafter referred to as “lower-car detection information” in thisembodiment) from the upper-car speed sensor 73, the lower-car speedsensor 74, the lower-car position sensor 76, and the inter-car distancesensor 91, whether or not the lower car 72 will collide against theupper car 71, and outputs an actuation signal to the lower-car safetydevice 78 upon predicting that a collision will occur. Otherwise, thisembodiment is of the same construction as Embodiment 7.

In the elevator apparatus as described above, the output portion 79predicts whether or not a collision will occur between the upper car 71and the lower car 72 based on the information from the inter-cardistance sensor 91, making it possible to predict with improvedreliability whether or not a collision will occur between the upper car71 and the lower car 72.

It should be noted that the door closed sensor 58 of Embodiment 3 may beapplied to the elevator apparatus as described in Embodiments 6 through8 so that the output portion is input with the open/closed detectionsignal. It is also possible to apply the break detection lead wire 61 ofEmbodiment 4 here as well so that the output portion is input with therope break signal.

While the drive portion in Embodiments 2 through 8 described above isdriven by utilizing the electromagnetic repulsion force or theelectromagnetic attraction force between the first electromagneticportion 49 and the second electromagnetic portion 50, the drive portionmay be driven by utilizing, for example, an eddy current generated in aconductive repulsion plate. In this case, as shown in FIG. 15, a pulsedcurrent is supplied as an actuation signal to the electromagnet 48, andthe movable portion 40 is displaced through the interaction between aneddy current generated in a repulsion plate 51 fixed to the movableportion 40 and the magnetic field from the electromagnet 48.

While in Embodiments 2 through 8 described above the car speed detectingmeans is provided in the hoistway 1, it may also be mounted on the car.In this case, the speed detection signal from the car speed detectingmeans is transmitted to the output portion through the control cable.

Embodiment 9

FIG. 16 is a plan view showing a safety device according to Embodiment 9of the present invention. Here, a safety device 155 has the wedge 34, anactuator portion 156 connected to a lower portion of the wedge 34, andthe guide portion 36 arranged above the wedge 34 and fixed to the car 3.The actuator portion 156 is vertically movable with respect to the guideportion 36 together with the wedge 34.

The actuator portion 156 has a pair of contact portions 157 capable ofmoving into and away from contact with the car guide rail 2, a pair oflink members 158 a, 158 b each connected to one of the contact portions157, an actuating mechanism 159 for displacing the link member 158 arelative to the other link member 158 b such that the respective contactportions 157 move into and away from contact with the car guide rail 2,and a support portion 160 supporting the contact portions 157, the linkmembers 158 a, 158 b, and the actuating mechanism 159. A horizontalshaft 170, which passes through the wedge 34, is fixed to the supportportion 160. The wedge 34 is capable of reciprocating displacement inthe horizontal direction with respect to the horizontal shaft 170.

The link members 158 a, 158 b cross each other at a portion between oneend to the other end portion thereof. Further, provided to the supportportion 160 is a connection member 161 which pivotably connects the linkmember 158 a, 158 b together at the portion where the link members 158a, 158 b cross each other. Further, the link member 158 a is provided soas to be pivotable with respect to the other link member 158 b about theconnection member 161.

As the respective other end portions of the link member 158 a, 158 b aredisplaced so as to approach each other, each contact portion 157 isdisplaced into contact with the car guide rail 2. Likewise, as therespective other end portions of the link member 158 a, 158 b aredisplaced so as to separate away from each other, each contact portion157 is displaced away from the car guide rail 2.

The actuating mechanism 159 is arranged between the respective other endportions of the link members 158 a, 158 b. Further, the actuatingmechanism 159 is supported by each of the link members 158 a, 158 b.Further, the actuating mechanism 159 includes a rod-like movable portion162 connected to the link member 158 a, and a drive portion 163 fixed tothe other link member 158 band adapted to displace the movable portion162 in a reciprocating manner. The actuating mechanism 159 is pivotableabout the connection member 161 together with the link members 158 a,158 b.

The movable portion 162 has a movable iron core 164 accommodated withinthe drive portion 163, and a connecting rod 165 connecting the movableiron core 164 and the link member 158 b to each other. Further, themovable portion 162 is capable of reciprocating displacement between acontact position where the contact portions 157 come into contact withthe car guide rail 2 and a separated position where the contact portions157 are separated away from contact with the car guide rail 2.

The drive portion 163 has a stationary iron core 166 including a pair ofregulating portions 166 a and 166 b regulating the displacement of themovable iron core 164 and a side wall portion 166 c that connects theregulating members 166 a, 166 b to each other and, surrounding themovable iron core 164, a first coil 167 which is accommodated within thestationary iron core 166 and which, when supplied with electric current,causes the movable iron core 164 to be displaced into contact with theregulating portion 166 a, a second coil 168 which is accommodated withinthe stationary iron core 166 and which, when supplied with electriccurrent, causes the movable iron core 164 to be displaced into contactwith the other regulating portion 166 b, and an annular permanent magnet169 arranged between the first coil 167 and the second coil 168.

The regulating member 166 a is so arranged that the movable iron core164 abuts on the regulating member 166 a when the movable portion 162 isat the separated position. Further, the other regulating member 166 b isso arranged that the movable iron core 164 abuts on the regulatingmember 166 b when the movable portion 162 is at the contact position.

The first coil 167 and the second coil 168 are annular electromagnetsthat surround the movable portion 162. Further, the first coil 167 isarranged between the permanent magnet 169 and the regulating portion 166a, and the second coil 168 is arranged between the permanent magnet 169and the other regulating portion 166 b.

With the movable iron core 164 abutting on the regulating portion 166 a,a space serving as a magnetic resistance exists between the movable ironcore 164 and the other regulating member 166 b, with the result that theamount of magnetic flux generated by the permanent magnet 169 becomeslarger on the first coil 167 side than on the second coil 168 side.Thus, the movable iron core 164 is retained in position while stillabutting on the regulating member 166 a.

Further, with the movable iron core 164 abutting on the other regulatingportion 166 b, a space serving as a magnetic resistance exists betweenthe movable iron core 164 and the regulating member 166 a, with theresult that the amount of magnetic flux generated by the permanentmagnet 169 becomes larger on the second coil 168 side than on the firstcoil 167 side. Thus, the movable iron core 164 is retained in positionwhile still abutting on the other regulating member 166 b.

Electric power serving as an actuation signal from the output portion 32can be input to the second coil 168. When input with the actuationsignal, the second coil 168 generates a magnetic flux acting against theforce that keeps the movable iron core 164 in abutment with theregulating portion 166 a. Further, electric power serving as a recoverysignal from the output portion 32 can be input to the first coil 167.When input with the recovery signal, the first coil 167 generates amagnetic flux acting against the force that keeps the movable iron core164 in abutment with the other regulating portion 166 b.

Otherwise, this embodiment is of the same construction as Embodiment 2.

Next, operation is described. During normal operation, the movableportion 162 is located at the separated position, with the movable ironcore 164 being held in abutment on the regulating portion 166 a by theholding force of the permanent magnet 169. With the movable iron core164 abutting on the regulating portion 166 a, the wedge 34 is maintainedat a spacing from the guide portion 36 and separated away from the carguide rail 2.

Thereafter, as in Embodiment 2, by outputting an actuation signal toeach safety device 155 from the output portion 32, electric current issupplied to the second coil 168. This generates a magnetic flux aroundthe second coil 168, which causes the movable iron core 164 to bedisplaced toward the other regulating portion 166 b, that is, from theseparated position to the contact position. As this happens, the contactportions 157 are displaced so as to approach each other, coming intocontact with the car guide rail 2. Braking is thus applied to the wedge34 and the actuator portion 155.

Thereafter, the guide portion 36 continues its descent, thus approachingthe wedge 34 and the actuator portion 155. As a result, the wedge 34 isguided along the inclined surface 44, causing the car guide rail 2 to beheld between the wedge 34 and the contact surface 45. Thereafter, thecar 3 is braked through operations identical to those of Embodiment 2.

During the recovery phase, a recovery signal is transmitted from theoutput portion 32 to the first coil 167. As a result, a magnetic flux isgenerated around the first coil 167, causing the movable iron core 164to be displaced from the contact position to the separated position.Thereafter, the press contact of the wedge 34 and the contact surface 45with the car guide rail 2 is released in the same manner as inEmbodiment 2.

In the elevator apparatus as described above, the actuating mechanism159 causes the pair of contact portions 157 to be displaced through theintermediation of the link members 158 a, 158 b, whereby, in addition tothe same effects as those of Embodiment 2, it is possible to reduce thenumber of actuating mechanisms 159 required for displacing the pair ofcontact portions 157.

Embodiment 10

FIG. 17 is a partially cutaway side view showing a safety deviceaccording to Embodiment 10 of the present invention. Referring to FIG.17, a safety device 175 has the wedge 34, an actuator portion 176connected to a lower portion of the wedge 34, and the guide portion 36arranged above the wedge 34 and fixed to the car 3.

The actuator portion 176 has the actuating mechanism 159 constructed inthe same manner as that of Embodiment 9, and a link member 177displaceable through displacement of the movable portion 162 of theactuating mechanism 159.

The actuating mechanism 159 is fixed to a lower portion of the car 3 soas to allow reciprocating displacement of the movable portion 162 in thehorizontal direction with respect to the car 3. The link member 177 ispivotably provided to a stationary shaft 180 fixed to a lower portion ofthe car 3. The stationary shaft 180 is arranged below the actuatingmechanism 159.

The link member 177 has a first link portion 178 and a second linkportion 179 which extend in different directions from the stationaryshaft 180 taken as the start point. The overall configuration of thelink member 177 is substantially a prone shape. That is, the second linkportion 179 is fixed to the first link portion 178, and the first linkportion 178 and the second link portion 179 are integrally pivotableabout the stationary shaft 180.

The length of the first link portion 178 is larger than that of thesecond link portion 179. Further, an elongate hole 182 is provided atthe distal end portion of the first link portion 178. A slide pin 183,which is slidably passed through the elongate hole 182, is fixed to alower portion of the wedge 34. That is, the wedge 34 is slidablyconnected to the distal end portion of the first link portion 178. Thedistal end portion of the movable portion 162 is pivotably connected tothe distal end portion of the second link portion 179 through theintermediation of a connecting pin 181.

The link member 177 is capable of reciprocating movement between aseparated position where it keeps the wedge 34 separated away from andbelow the guide portion 36 and an actuating position where it causes thewedge 34 to wedge in between the car guide rail and the guide portion36. The movable portion 162 is projected from the drive portion 163 whenthe link member 177 is at the separated position, and it is retractedinto the drive portion 163 when the link member is at the actuatingposition.

Next, operation is described. During normal operation, the link member177 is located at the separated position due to the retracting motion ofthe movable portion 162 into the drive portion 163. At this time, thewedge 34 is maintained at a spacing from the guide portion 36 andseparated away from the car guide rail.

Thereafter, in the same manner as in Embodiment 2, an actuation signalis output from the output portion 32 to each safety device 175, causingthe movable portion 162 to advance. As a result, the link member 177 ispivoted about the stationary shaft 180 for displacement into theactuating position. This causes the wedge 34 to come into contact withthe guide portion 36 and the car guide rail, wedging in between theguide portion 36 and the car guide rail. Braking is thus applied to thecar 3.

During the recovery phase, a recovery signal is transmitted from theoutput portion 32 to each safety device 175, causing the movable portion162 to be urged in the retracting direction. The car 3 is raised in thisstate, thus releasing the wedging of the wedge 34 in between the guideportion 36 and the car guide rail.

The above-described elevator apparatus also provides the same effects asthose of Embodiment 2.

Embodiment 11

FIG. 18 is a schematic diagram showing an elevator apparatus accordingto Embodiment 11 of the present invention. In FIG. 18, a hoistingmachine 101 serving as a driving device and a control panel 102 areprovided in an upper portion within the hoistway 1. The control panel102 is electrically connected to the hoisting machine 101 and controlsthe operation of the elevator. The hoisting machine 101 has a drivingdevice main body 103 including a motor and a driving sheave 104 rotatedby the driving device main body 103. A plurality of main ropes 4 arewrapped around the sheave 104. The hoisting machine 101 further includesa deflector sheave 105 around which each main rope 4 is wrapped, and ahoisting machine braking device (deceleration braking device) 106 forbraking the rotation of the driving sheave 104 to decelerate the car 3.The car 3 and a counter weight 107 are suspended in the hoistway 1 bymeans of the main ropes 4. The car 3 and the counterweight 107 areraised and lowered in the hoistway 1 by driving the hoisting machine101.

The safety device 33, the hoisting machine braking device 106, and thecontrol panel 102 are electrically connected to a monitor device 108that constantly monitors the state of the elevator. A car positionsensor 109, a car speed sensor 110, and a car acceleration sensor 111are also electrically connected to the monitor device 108. The carposition sensor 109, the car speed sensor 110, and the car accelerationsensor 111 respectively serve as a car position detecting portion fordetecting the speed of the car 3, a car speed detecting portion fordetecting the speed of the car 3, and a car acceleration detectingportion for detecting the acceleration of the car 3. The car positionsensor 109, the car speed sensor 110, and the car acceleration sensor111 are provided in the hoistway 1.

Detection means 112 for detecting the state of the elevator includes thecar position sensor 109, the car speed sensor 110, and the caracceleration sensor 111. Any of the following may be used for the carposition sensor 109: an encoder that detects the position of the car 3by measuring the amount of rotation of a rotary member that rotates asthe car 3 moves; a linear encoder that detects the position of the car 3by measuring the amount of linear displacement of the car 3; an opticaldisplacement measuring device which includes, for example, a projectorand a photodetector provided in the hoistway 1 and a reflection plateprovided in the car 3, and which detects the position of the car 3 bymeasuring how long it takes for light projected from the projector toreach the photodetector.

The monitor device 108 includes a memory portion 113 and an outputportion (calculation portion) 114. The memory portion 113 stores inadvance a variety of (in this embodiment, two) abnormality determinationcriteria (set data) serving as criteria for judging whether or not thereis an abnormality in the elevator. The output portion 114 detectswhether or not there is an abnormality in the elevator based oninformation from the detection means 112 and the memory portion 113. Thetwo kinds of abnormality determination criteria stored in the memoryportion 113 in this embodiment are car speed abnormality determinationcriteria relating to the speed of the car 3 and car accelerationabnormality determination criteria relating to the acceleration of thecar 3.

FIG. 19 is a graph showing the car speed abnormality determinationcriteria stored in the memory portion 113 of FIG. 18. In FIG. 19, anascending/descending section of the car 3 in the hoistway 1 (a sectionbetween one terminal floor and an other terminal floor) includesacceleration/deceleration sections and a constant speed section locatedbetween the acceleration/deceleration sections. The car 3accelerates/decelerates in the acceleration/deceleration sectionsrespectively located in the vicinity of the one terminal floor and theother terminal floor. The car 3 travels at a constant speed in theconstant speed section.

The car speed abnormality determination criteria has three detectionpatterns each associated with the position of the car 3. That is, anormal speed detection pattern (normal level) 115 that is the speed ofthe car 3 during normal operation, a first abnormal speed detectionpattern (first abnormal level) 116 having a larger value than the normalspeed detection pattern 115, and a second abnormal speed detectionpattern (second abnormal level) 117 having a larger value than the firstabnormal speed detection pattern 116 are set, each in association withthe position of the car 3.

The normal speed detection pattern 115, the first abnormal speeddetection pattern 116, and a second abnormal speed detection pattern 117are set so as to have a constant value in the constant speed section,and to have a value continuously becoming smaller toward the terminalfloor in each of the acceleration and deceleration sections. Thedifference in value between the first abnormal speed detection pattern116 and the normal speed detection pattern 115, and the difference invalue between the second abnormal speed detection pattern 117 and thefirst abnormal speed detection pattern 116, are set to be substantiallyconstant at all locations in the ascending/descending section.

FIG. 20 is a graph showing the car acceleration abnormalitydetermination criteria stored in the memory portion 113 of FIG. 18. InFIG. 20, the car acceleration abnormality determination criteria hasthree detection patterns each associated with the position of the car 3.That is, a normal acceleration detection pattern (normal level) 118 thatis the acceleration of the car 3 during normal operation, a firstabnormal acceleration detection pattern (first abnormal level) 119having a larger value than the normal acceleration detection pattern118, and a second abnormal acceleration detection pattern (secondabnormal level) 120 having a larger value than the first abnormalacceleration detection pattern 119 are set, each in association with theposition of the car 3.

The normal acceleration detection pattern 118, the first abnormalacceleration detection pattern 119, and the second abnormal accelerationdetection pattern 120 are each set so as to have a value of zero in theconstant speed section, a positive value in one of theacceleration/deceleration section, and a negative value in the otheracceleration/deceleration section. The difference in value between thefirst abnormal acceleration detection pattern 119 and the normalacceleration detection pattern 118, and the difference in value betweenthe second abnormal acceleration detection pattern 120 and the firstabnormal acceleration detection pattern 119, are set to be substantiallyconstant at all locations in the ascending/descending section.

That is, the memory portion 113 stores the normal speed detectionpattern 115, the first abnormal speed detection pattern 116, and thesecond abnormal speed detection pattern 117 as the car speed abnormalitydetermination criteria, and stores the normal acceleration detectionpattern 118, the first abnormal acceleration detection pattern 119, andthe second abnormal acceleration detection pattern 120 as the caracceleration abnormality determination criteria.

The safety device 33, the control panel 102, the hoisting machinebraking device 106, the detection means 112, and the memory portion 113are electrically connected to the output portion 114. Further, aposition detection signal, a speed detection signal, and an accelerationdetection signal are input to the output portion 114 continuously overtime from the car position sensor 109, the car speed sensor 110, and thecar acceleration sensor 111. The output portion 114 calculates theposition of the car 3 based on the input position detection signal. Theoutput portion 114 also calculates the speed of the car 3 and theacceleration of the car 3 based on the input speed detection signal andthe input acceleration detection signal, respectively, as a variety of(in this example, two) abnormality determination factors.

The output portion 114 outputs an actuation signal (trigger signal) tothe hoisting machine braking device 106 when the speed of the car 3exceeds the first abnormal speed detection pattern 116, or when theacceleration of the car 3 exceeds the first abnormal accelerationdetection pattern 119. At the same time, the output portion 114 outputsa stop signal to the control panel 102 to stop the drive of the hoistingmachine 101. When the speed of the car 3 exceeds the second abnormalspeed detection pattern 117, or when the acceleration of the car 3exceeds the second abnormal acceleration detection pattern 120, theoutput portion 114 outputs an actuation signal to the hoisting machinebraking device 106 and the safety device 33. That is, the output portion114 determines to which braking means it should output the actuationsignals according to the degree of the abnormality in the speed and theacceleration of the car 3.

Otherwise, this embodiment is of the same construction as Embodiment 2.

Next, operation is described. When the position detection signal, thespeed detection signal, and the acceleration detection signal are inputto the output portion 114 from the car position sensor 109, the carspeed sensor 110, and the car acceleration sensor 111, respectively, theoutput portion 114 calculates the position, the speed, and theacceleration of the car 3 based on the respective detection signals thusinput. After that, the output portion 114 compares the car speedabnormality determination criteria and the car acceleration abnormalitydetermination criteria obtained from the memory portion 113 with thespeed and the acceleration of the car 3 calculated based on therespective detection signals input. Through this comparison, the outputportion 114 detects whether or not there is an abnormality in either thespeed or the acceleration of the car 3.

During normal operation, the speed of the car 3 has approximately thesame value as the normal speed detection pattern, and the accelerationof the car 3 has approximately the same value as the normal accelerationdetection pattern. Thus, the output portion 114 detects that there is noabnormality in either the speed or the acceleration of the car 3, andnormal operation of the elevator continues.

When, for example, the speed of the car 3 abnormally increases andexceeds the first abnormal speed detection pattern 116 due to somecause, the output portion 114 detects that there is an abnormality inthe speed of the car 3. Then, the output portion 114 outputs anactuation signal and a stop signal to the hoisting machine brakingdevice 106 and the control panel 102, respectively. As a result, thehoisting machine 101 is stopped, and the hoisting machine braking device106 is operated to brake the rotation of the driving sheave 104.

When the acceleration of the car 3 abnormally increases and exceeds thefirst abnormal acceleration set value 119, the output portion 114outputs an actuation signal and a stop signal to the hoisting machinebraking device 106 and the control panel 102, respectively, therebybraking the rotation of the driving sheave 104.

If the speed of the car 3 continues to increase after the actuation ofthe hoisting machine braking device 106 and exceeds the second abnormalspeed set value 117, the output portion 114 outputs an actuation signalto the safety device 33 while still outputting the actuation signal tothe hoisting machine braking device 106. Thus, the safety device 33 isactuated and the car 3 is braked through the same operation as that ofEmbodiment 2.

Further, when the acceleration of the car 3 continues to increase afterthe actuation of the hoisting machine braking device 106, and exceedsthe second abnormal acceleration set value 120, the output portion 114outputs an actuation signal to the safety device 33 while stilloutputting the actuation signal to the hoisting machine braking device106. Thus, the safety device 33 is actuated.

With such an elevator apparatus, the monitor device 108 obtains thespeed of the car 3 and the acceleration of the car 3 based on theinformation from the detection means 112 for detecting the state of theelevator. When the monitor device 108 judges that there is anabnormality in the obtained speed of the car 3 or the obtainedacceleration of the car 3, the monitor device 108 outputs an actuationsignal to at least one of the hoisting machine braking device 106 andthe safety device 33. That is, judgment of the presence or absence of anabnormality is made by the monitor device 108 separately for a varietyof abnormality determination factors such as the speed of the car andthe acceleration of the car. Accordingly, an abnormality in the elevatorcan be detected earlier and more reliably. Therefore, it takes a shortertime for the braking force on the car 3 to be generated after occurrenceof an abnormality in the elevator.

Further, the monitor device 108 includes the memory portion 113 thatstores the car speed abnormality determination criteria used for judgingwhether or not there is an abnormality in the speed of the car 3, andthe car acceleration abnormality determination criteria used for judgingwhether or not there is an abnormality in the acceleration of the car 3.Therefore, it is easy to change the judgment criteria used for judgingwhether or not there is an abnormality in the speed and the accelerationof the car 3, respectively, allowing easy adaptation to design changesor the like of the elevator.

Further, the following patterns are set for the car speed abnormalitydetermination criteria: the normal speed detection pattern 115, thefirst abnormal speed detection pattern 116 having a larger value thanthe normal speed detection pattern 115, and the second abnormal speeddetection pattern 117 having a larger value than the first abnormalspeed detection pattern 116. When the speed of the car 3 exceeds thefirst abnormal speed detection pattern 116, the monitor device 108outputs an actuation signal to the hoisting machine braking device 106,and when the speed of the car 3 exceeds the second abnormal speeddetection pattern 117, the monitor device 108 outputs an actuationsignal to the hoisting machine braking device 106 and the safety device33. Therefore, the car 3 can be braked stepwise according to the degreeof this abnormality in the speed of the car 3. As a result, thefrequency of large shocks exerted on the car 3 can be reduced, and thecar 3 can be more reliably stopped.

Further, the following patterns are set for the car accelerationabnormality determination criteria: the normal acceleration detectionpattern 118, the first abnormal acceleration detection pattern 119having a larger value than the normal acceleration detection pattern118, and the second abnormal acceleration detection pattern 120 having alarger value than the first abnormal acceleration detection pattern 119.When the acceleration of the car 3 exceeds the first abnormalacceleration detection pattern 119, the monitor device 108 outputs anactuation signal to the hoisting machine braking device 106, and whenthe acceleration of the car 3 exceeds the second abnormal accelerationdetection pattern 120, the monitor device 108 outputs an actuationsignal to the hoisting machine braking device 106 and the safety device33. Therefore, the car 3 can be braked stepwise according to the degreeof an abnormality in the acceleration of the car 3. Normally, anabnormality occurs in the acceleration of the car 3 before anabnormality occurs in the speed of the car 3. As a result, the frequencyof large shocks exerted on the car 3 can be reduced, and the car 3 canbe more reliably stopped.

Further, the normal speed detection pattern 115, the first abnormalspeed detection pattern 116, and the second abnormal speed detectionpattern 117 are each set in association with the position of the car 3.Therefore, the first abnormal speed detection pattern 116 and the secondabnormal speed detection pattern 117 each can be set in association withthe normal speed detection pattern 115 at all locations in theascending/descending section of the car 3. In theacceleration/deceleration sections, in particular, the first abnormalspeed detection pattern 116 and the second abnormal speed detectionpattern 117 each can be set to a relatively small value because thenormal speed detection pattern 115 has a small value. As a result, theimpact acting on the car 3 upon braking can be mitigated.

It should be noted that in the above-described example, the car speedsensor 110 is used when the monitor 108 obtains the speed of the car 3.However, instead of using the car speed sensor 110, the speed of the car3 may be obtained from the position of the car 3 detected by the carposition sensor 109. That is, the speed of the car 3 may be obtained bydifferentiating the position of the car 3 calculated by using theposition detection signal from the car position sensor 109.

Further, in the above-described example, the car acceleration sensor 111is used when the monitor 108 obtains the acceleration of the car 3.However, instead of using the car acceleration sensor 111, theacceleration of the car 3 may be obtained from the position of the car 3detected by the car position sensor 109. That is, the acceleration ofthe car 3 may be obtained by differentiating, twice, the position of thecar 3 calculated by using the position detection signal from the carposition sensor 109.

Further, in the above-described example, the output portion 114determines to which braking means it should output the actuation signalsaccording to the degree of the abnormality in the speed and accelerationof the car 3 constituting the abnormality determination factors.However, the braking means to which the actuation signals are to beoutput may be determined in advance for each abnormality determinationfactor.

Embodiment 12

FIG. 21 is a schematic diagram showing an elevator apparatus accordingto Embodiment 12 of the present invention. In FIG. 21, a plurality ofhall call buttons 125 are provided in the hall of each floor. Aplurality of destination floor buttons 126 are provided in the car 3. Amonitor device 127 has the output portion 114. An abnormalitydetermination criteria generating device 128 for generating a car speedabnormality determination criteria and a car acceleration abnormalitydetermination criteria is electrically connected to the output portion114. The abnormality determination criteria generating device 128 iselectrically connected to each hall call button 125 and each destinationfloor button 126. A position detection signal is input to theabnormality determination criteria generating device 128 from the carposition sensor 109 via the output portion 114.

The abnormality determination criteria generating device 128 includes amemory portion 129 and a generation portion 130. The memory portion 129stores a plurality of car speed abnormality determination criteria and aplurality of car acceleration abnormality determination criteria, whichserve as abnormal judgment criteria for all the cases where the car 3ascends and descends between the floors. The generation portion 130selects a car speed abnormality determination criteria and a caracceleration abnormality determination criteria one by one from thememory portion 129, and outputs the car speed abnormality determinationcriteria and the car acceleration abnormality determination criteria tothe output portion 114.

Each car speed abnormality determination criteria has three detectionpatterns each associated with the position of the car 3, which aresimilar to those of FIG. 19 of Embodiment 11. Further, each caracceleration abnormality determination criteria has three detectionpatterns each associated with the position of the car 3, which aresimilar to those of FIG. 20 of Embodiment 11.

The generation portion 130 calculates a detection position of the car 3based on information from the car position sensor 109, and calculates atarget floor of the car 3 based on information from at least one of thehall call buttons 125 and the destination floor buttons 126. Thegeneration portion 130 selects one by one a car speed abnormalitydetermination criteria and a car acceleration abnormality determinationcriteria used for a case where the calculated detection position and thetarget floor are one and the other of the terminal floors.

Otherwise, this embodiment is of the same construction as Embodiment 11.

Next, operation is described. A position detection signal is constantlyinput to the generation portion 130 from the car position sensor 109 viathe output portion 114. When a passenger or the like selects any one ofthe hall call buttons 125 or the destination floor buttons 126 and acall signal is input to the generation portion 130 from the selectedbutton, the generation portion 130 calculates a detection position and atarget floor of the car 3 based on the input position detection signaland the input call signal, and selects one out of both a car speedabnormality determination criteria and a car acceleration abnormalitydetermination criteria. After that, the generation portion 130 outputsthe selected car speed abnormality determination criteria and theselected car acceleration abnormality determination criteria to theoutput portion 114.

The output portion 114 detects whether or not there is an abnormality inthe speed and the acceleration of the car 3 in the same way as inEmbodiment 11. Thereafter, this embodiment is of the same operation asEmbodiment 9.

With such an elevator apparatus, the car speed abnormality determinationcriteria and the car acceleration abnormality determination criteria aregenerated based on the information from at least one of the hall callbuttons 125 and the destination floor buttons 126. Therefore, it ispossible to generate the car speed abnormality determination criteriaand the car acceleration abnormality determination criteriacorresponding to the target floor. As a result, the time it takes forthe braking force on the car 3 to be generated after occurrence of anabnormality in the elevator can be reduced even when a different targetfloor is selected.

It should be noted that in the above-described example, the generationportion 130 selects one out of both the car speed abnormalitydetermination criteria and car acceleration abnormality determinationcriteria from among a plurality of car speed abnormality determinationcriteria and a plurality of car acceleration abnormality determinationcriteria stored in the memory portion 129. However, the generationportion may directly generate an abnormal speed detection pattern and anabnormal acceleration detection pattern based on the normal speedpattern and the normal acceleration pattern of the car 3 generated bythe control panel 102.

Embodiment 13

FIG. 22 is a schematic diagram showing an elevator apparatus accordingto Embodiment 13 of the present invention. In this example, each of themain ropes 4 is connected to an upper portion of the car 3 via a ropefastening device 131 (FIG. 23). The monitor device 108 is mounted on anupper portion of the car 3. The car position sensor 109, the car speedsensor 110, and a plurality of rope sensors 132 are electricallyconnected to the output portion 114. Rope sensors 132 are provided inthe rope fastening device 131, and each serve as a rope break detectingportion for detecting whether or not a break has occurred in each of theropes 4. The detection means 112 includes the car position sensor 109,the car speed sensor 110, and the rope sensors 132.

The rope sensors 132 each output a rope brake detection signal to theoutput portion 114 when the main ropes 4 break. The memory portion 113stores the car speed abnormality determination criteria similar to thatof Embodiment 11 shown in FIG. 19, and a rope abnormality determinationcriteria used as a reference for judging whether or not there is anabnormality in the main ropes 4.

A first abnormal level indicating a state where at least one of the mainropes 4 have broken, and a second abnormal level indicating a statewhere all of the main ropes 4 has broken are set for the ropeabnormality determination criteria.

The output portion 114 calculates the position of the car 3 based on theinput position detection signal. The output portion 114 also calculatesthe speed of the car 3 and the state of the main ropes 4 based on theinput speed detection signal and the input rope brake signal,respectively, as a variety of (in this example, two) abnormalitydetermination factors.

The output portion 114 outputs an actuation signal (trigger signal) tothe hoisting machine braking device 106 when the speed of the car 3exceeds the first abnormal speed detection pattern 116 (FIG. 19), orwhen at least one of the main ropes 4 breaks. When the speed of the car3 exceeds the second abnormal speed detection pattern 117 (FIG. 19), orwhen all of the main ropes 4 break, the output portion 114 outputs anactuation signal to the hoisting machine braking device 106 and thesafety device 33. That is, the output portion 114 determines to whichbraking means it should output the actuation signals according to thedegree of an abnormality in the speed of the car 3 and the state of themain ropes 4.

FIG. 23 is a diagram showing the rope fastening device 131 and the ropesensors 132 of FIG. 22. FIG. 24 is a diagram showing a state where oneof the main ropes 4 of FIG. 23 has broken. In FIGS. 23 and 24, the ropefastening device 131 includes a plurality of rope connection portions134 for connecting the main ropes 4 to the car 3. The rope connectionportions 134 each include an spring 133 provided between the main rope 4and the car 3. The position of the car 3 is displaceable with respect tothe main ropes 4 by the expansion and contraction of the springs 133.

The rope sensors 132 are each provided to the rope connection portion134. The rope sensors 132 each serve as a displacement measuring devicefor measuring the amount of expansion of the spring 133. Each ropesensor 132 constantly outputs a measurement signal corresponding to theamount of expansion of the spring 133 to the output portion 114. Ameasurement signal obtained when the expansion of the spring 133returning to its original state has reached a predetermined amount isinput to the output portion 114 as a break detection signal. It shouldbe noted that each of the rope connection portions 134 may be providedwith a scale device that directly measures the tension of the main ropes4.

Otherwise, this embodiment is of the same construction as Embodiment 11.

Next, operation is described. When the position detection signal, thespeed detection signal, and the break detection signal are input to theoutput portion 114 from the car position sensor 109, the car speedsensor 110, and each rope sensor 131, respectively, the output portion114 calculates the position of the car 3, the speed of the car 3, andthe number of main ropes 4 that have broken based on the respectivedetection signals thus input. After that, the output portion 114compares the car speed abnormality determination criteria and the ropeabnormality determination criteria obtained from the memory portion 113with the speed of the car 3 and the number of broken main ropes 4calculated based on the respective detection signals input. Through thiscomparison, the output portion 114 detects whether or not there is anabnormality in both the speed of the car 3 and the state of the mainropes 4.

During normal operation, the speed of the car 3 has approximately thesame value as the normal speed detection pattern, and the number ofbroken main ropes 4 is zero. Thus, the output portion 114 detects thatthere is no abnormality in either the speed of the car 3 or the state ofthe main ropes 4, and normal operation of the elevator continues.

When, for example, the speed of the car 3 abnormally increases andexceeds the first abnormal speed detection pattern 116 (FIG. 19) forsome reason, the output portion 114 detects that there is an abnormalityin the speed of the car 3. Then, the output portion 114 outputs anactuation signal and a stop signal to the hoisting machine brakingdevice 106 and the control panel 102, respectively. As a result, thehoisting machine 101 is stopped, and the hoisting machine raking device106 is operated to brake the rotation of the driving sheave 104.

Further, when at least one of the main ropes 4 has broken, the outputportion 114 outputs an actuation signal and a stop signal to thehoisting machine braking device 106 and the control panel 102,respectively, thereby braking the rotation of the driving sheave 104.

If the speed of the car 3 continues to increase after the actuation ofthe hoisting machine braking device 106 and exceeds the second abnormalspeed set value 117 (FIG. 19), the output portion 114 outputs anactuation signal to the safety device 33 while still outputting theactuation signal to the hoisting machine braking device 106. Thus, thesafety device 33 is actuated and the car 3 is braked through the sameoperation as that of Embodiment 2.

Further, if all the main ropes 4 break after the actuation of thehoisting machine braking device 106, the output portion 114 outputs anactuation signal to the safety device 33 while still outputting theactuation signal to the hoisting machine braking device 106. Thus, thesafety device 33 is actuated.

With such an elevator apparatus, the monitor device 108 obtains thespeed of the car 3 and the state of the main ropes 4 based on theinformation from the detection means 112 for detecting the state of theelevator. When the monitor device 108 judges that there is anabnormality in the obtained speed of the car 3 or the obtained state ofthe main ropes 4, the monitor device 108 outputs an actuation signal toat least one of the hoisting machine braking device 106 and the safetydevice 33. This means that the number of targets for abnormalitydetection increases, allowing abnormality detection of not only thespeed of the car 3 but also the state of the main ropes 4. Accordingly,an abnormality in the elevator can be detected earlier and morereliably. Therefore, it takes a shorter time for the braking force onthe car 3 to be generated after occurrence of an abnormality in theelevator.

It should be noted that in the above-described example, the rope sensor132 is disposed in the rope fastening device 131 provided to the car 3.However, the rope sensor 132 may be disposed in a rope fastening deviceprovided to the counterweight 107.

Further, in the above-described example, the present invention isapplied to an elevator apparatus of the type in which the car 3 and thecounterweight 107 are suspended in the hoistway 1 by connecting one endportion and the other end portion of the main rope 4 to the car 3 andthe counterweight 107, respectively. However, the present invention mayalso be applied to an elevator apparatus of the type in which the car 3and the counterweight 107 are suspended in the hoistway 1 by wrappingthe main rope 4 around a car suspension sheave and a counterweightsuspension sheave, with one end portion and the other end portion of themain rope 4 connected to structures arranged in the hoistway 1. In thiscase, the rope sensor is disposed in the rope fastening device providedto the structures arranged in the hoistway 1.

Embodiment 14

FIG. 25 is a schematic diagram showing an elevator apparatus accordingto Embodiment 14 of the present invention. In this example, a ropesensor 135 serving as a rope brake detecting portion is constituted bylead wires embedded in each of the main ropes 4. Each of the lead wiresextends in the longitudinal direction of the rope 4. Both end portion ofeach lead wire are electrically connected to the output portion 114. Aweak current flows in the lead wires. Cut-off of current flowing in eachof the lead wires is input as a rope brake detection signal to theoutput portion 114.

Otherwise, this embodiment is of the same construction as Embodiment 13.

With such an elevator apparatus, a break in any main rope 4 is detectedbased on cutting off of current supply to any lead wire embedded in themain ropes 4. Accordingly, whether or not the rope has broken is morereliably detected without being affected by a change of tension of themain ropes 4 due to acceleration and deceleration of the car 3.

Embodiment 15

FIG. 26 is a schematic diagram showing an elevator apparatus accordingto Embodiment 15 of the present invention. In FIG. 26, the car positionsensor 109, the car speed sensor 110, and a door sensor 140 areelectrically connected to the output portion 114. The door sensor 140serves as an entrance open/closed detecting portion for detectingopen/closed of the car entrance 26. The detection means 112 includes thecar position sensor 109, the car speed sensor 110, and the door sensor140.

The door sensor 140 outputs a door-closed detection signal to the outputportion 114 when the car entrance 26 is closed. The memory portion 113stores the car speed abnormality determination criteria similar to thatof Embodiment 11 shown in FIG. 19, and an entrance abnormalitydetermination criteria used as a reference for judging whether or notthere is an abnormality in the open/close state of the car entrance 26.If the car ascends/descends while the car entrance 26 is not closed, theentrance abnormality determination criteria regards this as an abnormalstate.

The output portion 114 calculates the position of the car 3 based on theinput position detection signal. The output portion 114 also calculatesthe speed of the car 3 and the state of the car entrance 26 based on theinput speed detection signal and the input door-closing detectionsignal, respectively, as a variety of (in this example, two) abnormalitydetermination factors.

The output portion 114 outputs an actuation signal to the hoistingmachine braking device 104 if the car ascends/descends while the carentrance 26 is not closed, or if the speed of the car 3 exceeds thefirst abnormal speed detection pattern 116 (FIG. 19). If the speed ofthe car 3 exceeds the second abnormal speed detection pattern 117 (FIG.19), the output portion 114 outputs an actuation signal to the hoistingmachine braking device 106 and the safety device 33.

FIG. 27 is a perspective view of the car 3 and the door sensor 140 ofFIG. 26. FIG. 28 is a perspective view showing a state in which the carentrance 26 of FIG. 27 is open. In FIGS. 27 and 28, the door sensor 140is provided at an upper portion of the car entrance 26 and in the centerof the car entrance 26 with respect to the width direction of the car 3.The door sensor 140 detects displacement of each of the car doors 28into the door-closed position, and outputs the door-closed detectionsignal to the output portion 114.

It should be noted that a contact type sensor, a proximity sensor, orthe like may be used for the door sensor 140. The contact type sensordetects closing of the doors through its contact with a fixed portionsecured to each of the car doors 28. The proximity sensor detectsclosing of the doors without contacting the car doors 28. Further, apair of hall doors 142 for opening/closing a hall entrance 141 areprovided at the hall entrance 141. The hall doors 142 are engaged to thecar doors 28 by means of an engagement device (not shown) when the car 3rests at a hall floor, and are displaced together with the car doors 28.

Otherwise, this embodiment is of the same construction as Embodiment 11.

Next, operation is described. When the position detection signal, thespeed detection signal, and the door-closed detection signal are inputto the output portion 114 from the car position sensor 109, the carspeed sensor 110, and the door sensor 140, respectively, the outputportion 114 calculates the position of the car 3, the speed of the car3, and the state of the car entrance 26 based on the respectivedetection signals thus input. After that, the output portion 114compares the car speed abnormality determination criteria and the drivedevice state abnormality determination criteria obtained from the memoryportion 113 with the speed of the car 3 and the state of the car of thecar doors 28 calculated based on the respective detection signals input.Through this comparison, the output portion 114 detects whether or notthere is an abnormality in each of the speed of the car 3 and the stateof the car entrance 26.

During normal operation, the speed of the car 3 has approximately thesame value as the normal speed detection pattern, and the car entrance26 is closed while the car 3 ascends/descends. Thus, the output portion114 detects that there is no abnormality in each of the speed of the car3 and the state of the car entrance 26, and normal operation of theelevator continues.

When, for instance, the speed of the car 3 abnormally increases andexceeds the first abnormal speed detection pattern 116 (FIG. 19) forsome reason, the output portion 114 detects that there is an abnormalityin the speed of the car 3. Then, the output portion 114 outputs anactuation signal and a stop signal to the hoisting machine brakingdevice 106 and the control panel 102, respectively. As a result, thehoisting machine 101 is stopped, and the hoisting machine braking device106 is actuated to brake the rotation of the driving sheave 104.

Further, the output portion 114 also detects an abnormality in the carentrance 26 when the car 3 ascends/descends while the car entrance 26 isnot closed. Then, the output portion 114 outputs an actuation signal anda stop signal to the hoisting machine braking device 106 and the controlpanel 102, respectively, thereby braking the rotation of the drivingsheave 104.

When the speed of the car 3 continues to increase after the actuation ofthe hoisting machine braking device 106, and exceeds the second abnormalspeed set value 117 (FIG. 19), the output portion 114 outputs anactuation signal to the safety device 33 while still outputting theactuation signal to the hoisting machine braking device 106. Thus, thesafety device 33 is actuated and the car 3 is braked through the sameoperation as that of Embodiment 2.

With such an elevator apparatus, the monitor device 108 obtains thespeed of the car 3 and the state of the car entrance 26 based on theinformation from the detection means 112 for detecting the state of theelevator. When the monitor device 108 judges that there is anabnormality in the obtained speed of the car 3 or the obtained state ofthe car entrance 26, the monitor device 108 outputs an actuation signalto at least one of the hoisting machine braking device 106 and thesafety device 33. This means that the number of targets for abnormalitydetection increases, allowing abnormality detection of not only thespeed of the car 3 but also the state of the car entrance 26.Accordingly, abnormalities of the elevator can be detected earlier andmore reliably. Therefore, it takes less time for the braking force onthe car 3 to be generated after occurrence of an abnormality in theelevator.

It should be noted that while in the above-described example, the doorsensor 140 only detects the state of the car entrance 26, the doorsensor 140 may detect both the state of the car entrance 26 and thestate of the elevator hall entrance 141. In this case, the door sensor140 detects displacement of the elevator hall doors 142 into thedoor-closed position, as well as displacement of the car doors 28 intothe door-closed position. With this construction, abnormality in theelevator can be detected even when only the car doors 28 are displaceddue to a problem with the engagement device or the like that engages thecar doors 28 and the elevator hall doors 142 with each other.

Embodiment 16

FIG. 29 is a schematic diagram showing an elevator apparatus accordingto Embodiment 16 of the present invention. FIG. 30 is a diagram showingan upper portion of the hoistway 1 of FIG. 29. In FIGS. 29 and 30, apower supply cable 150 is electrically connected to the hoisting machine110. Drive power is supplied to the hoisting machine 101 via the powersupply cable 150 through control of the control panel 102.

A current sensor 151 serving as a drive device detection portion isprovided to the power supply cable 150. The current sensor 151 detectsthe state of the hoisting machine 101 by measuring the current flowingin the power supply cable 150. The current sensor 151 outputs to theoutput portion 114 a current detection signal (drive device statedetection signal) corresponding to the value of a current in the powersupply cable 150. The current sensor 151 is provided in the upperportion of the hoistway 1. A current transformer (CT) that measures aninduction current generated in accordance with the amount of currentflowing in the power supply cable 150 is used as the current sensor 151,for example.

The car position sensor 109, the car speed sensor 110, and the currentsensor 151 are electrically connected to the output portion 114. Thedetection means 112 includes the car position sensor 109, the car speedsensor 110, and the current sensor 151.

The memory portion 113 stores the car speed abnormality determinationcriteria similar to that of Embodiment 11 shown in FIG. 19, and a drivedevice abnormality determination criteria used as a reference fordetermining whether or not there is an abnormality in the state of thehoisting machine 101.

The drive device abnormality determination criteria has three detectionpatterns. That is, a normal level that is the current value flowing inthe power supply cable 150 during normal operation, a first abnormallevel having a larger value than the normal level, and a second abnormallevel having a larger value than the first abnormal level, are set forthe drive device abnormality determination criteria.

The output portion 114 calculates the position of the car 3 based on theinput position detection signal. The output portion 114 also calculatesthe speed of the car 3 and the state of the hoisting device 101 based onthe input speed detection signal and the input current detection signal,respectively, as a variety of (in this example, two) abnormalitydetermination factors.

The output portion 114 outputs an actuation signal (trigger signal) tothe hoisting machine braking device 106 when the speed of the car 3exceeds the first abnormal speed detection pattern 116 (FIG. 19), orwhen the amount of the current flowing in the power supply cable 150exceeds the value of the first abnormal level of the drive deviceabnormality determination criteria. When the speed of the car 3 exceedsthe second abnormal speed detection pattern 117 (FIG. 19), or when theamount of the current flowing in the power supply cable 150 exceeds thevalue of the second abnormal level of the drive device abnormalitydetermination criteria, the output portion 114 outputs an actuationsignal to the hoisting machine braking device 106 and the safety device33. That is, the output portion 114 determines to which braking means itshould output the actuation signals according to the degree ofabnormality in each of the speed of the car 3 and the state of thehoisting machine 101.

Otherwise, this embodiment is of the same construction as embodiment 11.

Next, operation is described. When the position detection signal, thespeed detection signal, and the current detection signal are input tothe output portion 114 from the car position sensor 109, the car speedsensor 110, and the current sensor 151, respectively, the output portion114 calculates the position of the car 3, the speed of the car 3, andthe amount of current flowing in the power supply cable 151 based on therespective detection signals thus input. After that, the output portion114 compares the car speed abnormality determination criteria and thedrive device state abnormality determination criteria obtained from thememory portion 113 with the speed of the car 3 and the amount of thecurrent flowing into the current supply cable 150 calculated based onthe respective detection signals input. Through this comparison, theoutput portion 114 detects whether or not there is an abnormality ineach of the speed of the car 3 and the state of the hoisting machine101.

During normal operation, the speed of the car 3 has approximately thesame value as the normal speed detection pattern 115 (FIG. 19), and theamount of current flowing in the power supply cable 150 is at the normallevel. Thus, the output portion 114 detects that there is no abnormalityin each of the speed of the car 3 and the state of the hoisting machine101, and normal operation of the elevator continues.

If, for instance, the speed of the car 3 abnormally increases andexceeds the first abnormal speed detection pattern 116 (FIG. 19) forsome reason, the output portion 114 detects that there is an abnormalityin the speed of the car 3. Then, the output portion 114 outputs anactuation signal and a stop signal to the hoisting machine brakingdevice 106 and the control panel 102, respectively. As a result, thehoisting machine 101 is stopped, and the hoisting machine braking device106 is actuated to brake the rotation of the driving sheave 104.

If the amount of current flowing in the power supply cable 150 exceedsthe first abnormal level in the drive device state abnormalitydetermination criteria, the output portion 114 outputs an actuationsignal and a stop signal to the hoisting machine braking device 106 andthe control panel 102, respectively, thereby braking the rotation of thedriving sheave 104.

When the speed of the car 3 continues to increase after the actuation ofthe hoisting machine braking device 106, and exceeds the second abnormalspeed set value 117 (FIG. 19), the output portion 114 outputs anactuation signal to the safety device 33 while still outputting theactuation signal to the hoisting machine braking device 106. Thus, thesafety device 33 is actuated and the car 3 is braked through the sameoperation as that of Embodiment 2.

When the amount of current flowing in the power supply cable 150 exceedsthe second abnormal level of the drive device state abnormalitydetermination criteria after the actuation of the hoisting machinebraking device 106, the output portion 114 outputs an actuation signalto the safety device 33 while still outputting the actuation signal tothe hoisting machine braking device 106. Thus, the safety device 33 isactuated.

With such an elevator apparatus, the monitor device 108 obtains thespeed of the car 3 and the state of the hoisting machine 101 based onthe information from the detection means 112 for detecting the state ofthe elevator. When the monitor device 108 judges that there is anabnormality in the obtained speed of the car 3 or the state of thehoisting machine 101, the monitor device 108 outputs an actuation signalto at least one of the hoisting machine braking device 106 and thesafety device 33. This means that the number of targets for abnormalitydetection increases, and it takes a shorter time for the braking forceon the car 3 to be generated after occurrence of an abnormality in theelevator.

It should be noted that in the above-described example, the state of thehoisting machine 101 is detected using the current sensor 151 formeasuring the amount of the current flowing in the power supply cable150. However the state of the hoisting machine 101 may be detected usinga temperature sensor for measuring the temperature of the hoistingmachine 101.

Further, in Embodiments 11 through 16 described above, the outputportion 114 outputs an actuation signal to the hoisting machine brakingdevice 106 before outputting an actuation signal to the safety device33. However, the output portion 114 may instead output an actuationsignal to one of the following brakes: a car brake for braking the car 3by gripping the car guide rail 2, which is mounted on the car 3independently of the safety device 33; a counterweight brake mounted onthe counterweight 107 for braking the counterweight 107 by gripping acounterweight guide rail for guiding the counterweight 107; and a ropebrake mounted in the hoistway 1 for braking the main ropes 4 by lockingup the main ropes 4.

Further, in Embodiments 1 through 16 described above, the electric cableis used as the transmitting means for supplying power from the outputportion to the safety device. However, a wireless communication devicehaving a transmitter provided at the output portion and a receiverprovided at the safety device may be used instead. Alternatively, anoptical fiber cable that transmits an optical signal may be used.

Embodiment 17

FIG. 31 is a schematic diagram showing an elevator apparatus accordingto Embodiment 17 of the present invention. Referring to the FIG. 31, agovernor sheave 201 as a pulley is provided in an upper portion of thehoistway 1. A tension pulley 202 as a pulley is provided in a lowerportion of the hoistway 1. A governor rope 203 is wound around thegovernor sheave 201 and the tension pulley 202. The opposite endportions of the governor rope 203 are connected to the car 3.Accordingly, the governor sheave 201 and the governor rope 202 are eachrotated at a speed in accordance with the traveling speed of the car 3.It should be noted that a rope produced by stranding thin metallicwires, a steel tape, or the like may be used as the governor rope 203.

The governor sheave 201 is provided with an encoder 204 serving as apulley sensor. The encoder 204 outputs a rotational position signalbased on the rotational position of the governor sheave 201. That is,the encoder 204 outputs a signal in accordance with the rotation of thegovernor sheave 201.

Provided at the lower end portion of the car 3 is a car speed sensor 205for directly detecting the speed of the car 3. Further, the car speedsensor 205 irradiates an oscillating wave as an energy wave toward alower end portion of the hoistway 1. Provided at the lower end portionof the hoistway 1 is a reflector 207 provided with a reflecting surface206 for reflecting the oscillating wave from the car speed sensor 205 tothe car speed sensor 205. That is, the car speed sensor 205 irradiatesan oscillating wave toward the reflecting surface 206 and receives theoscillating wave reflected by the reflecting surface 206 as a reflectedwave.

Here, when an oscillating wave is irradiated from the car speed sensor205 toward the reflecting surface 206 while the car 3 is traveling, dueto the Doppler effect, the frequency of the resulting reflected wavechanges according to the relative speed between the car speed sensor 205and the reflecting surface 206 and thus becomes different from thefrequency of the oscillating wave. Since the car speed sensor 205 isprovided to the car 3, and the reflecting surface 206 is provided at thelower end portion of the hoistway 1, the relative speed between the carspeed sensor 205 and the reflecting surface 206 can be used asrepresenting the speed of the car 3. That is, the speed of the car 3 canbe obtained by measuring the difference between the frequency of theoscillating wave and the frequency of the reflected wave thereof. Thecar speed sensor 205 used is a Doppler sensor that utilizes thephenomenon as described above. That is, the car speed sensor 205 used isa Doppler sensor that is capable of measuring the difference between therespective frequencies of the oscillating wave and reflected wave, forobtaining the speed of the car 3 on the basis of the difference infrequency. It should be noted that examples of the oscillating waveinclude a microwave, an electric wave, laser light, and an ultrasonicwave.

Mounted in the control panel 102 are a first speed detecting portion 208for obtaining the speed of the car 3 based on information from theencoder 204, a second car speed calculating circuit (second speeddetecting portion) 209 for obtaining the speed of the car 3 based oninformation from the car speed sensor 205, a slippage determiningcircuit 210 as a determination portion for determining thepresence/absence of slippage between the governor rope 203 and thegovernor sheave 201 on the basis of information on the speed of the car3 as obtained by each of the first speed detecting portion 208 and thesecond car speed calculating circuit 209, and a control device 211 forcontrolling the operation of the elevator based on information from thefirst speed detecting portion 208 and the slippage determining circuit210.

The first speed detecting portion 208 has a car position calculatingcircuit 212 for obtaining the position of the car 3 based on the inputof the rotational position signal from the governor sheave 201, and afirst car speed calculating circuit 213 for obtaining the speed of thecar 3 based on information on the position of the car 3 obtained fromthe car position circulating circuit 210.

The second car speed calculating circuit 209 obtains the speed of thecar 3 based on information on the frequency difference from the carspeed sensor 205.

The slippage determining circuit 210 is inputted with information on thespeed of the car 3 obtained by the first car speed calculating circuit213, and information on the speed of the car 3 obtained by the secondcar speed calculating circuit 209. Further, a reference value fordetermining the presence/absence of slippage between the governor sheave201 and the governor rope 203 is set in advance to the slippagedetermining circuit 210.

The slippage determining circuit 210 detects the presence/absence ofslippage between the governor sheave 201 and the governor rope 203through a comparison between the information on the speed of the car 3respectively obtained from the first and second car speed calculatingcircuits 213, 209. That is, the slippage determining circuit 210 obtainsthe difference between the speeds of the car 3 respectively obtainedfrom the first and second car speed calculating circuits 213, 209, anddetermines that no slippage has occurred when the difference in speed issmaller than the reference value and that slippage has occurred when thedifference in speed is equal to or larger than the reference value.

The control device 211 is inputted with information on the position ofthe car 3 obtained by the car position calculating circuit 212,information on the speed of the car 3 obtained by the first car speedcalculating circuit 213, and information on the presence/absence ofslippage as determined by the slippage determining circuit 210. Further,the control device 211 is adapted to control the operation of theelevator based on the inputted information on the position of the car 3,the speed of the car 3, and the presence/absence of slippage.

The control device 211 stores the same car speed abnormality judgmentcriteria as those of Embodiment 11 shown in FIG. 19. The control device211 outputs an actuation signal (trigger signal) to the hoisting machinebraking device 104 (FIG. 18) when the speed of the car 3 as obtainedfrom the first car speed calculating circuit 213 exceeds the firstabnormal speed detection pattern 116 (FIG. 19). Further, when the speedof the car 3 as obtained from the first car speed calculating circuit213 exceeds the second abnormal speed detection pattern 117 (FIG. 19),the control device 211 outputs an actuation signal to the safety device33 while continuing to output the actuation signal to the hoistingmachine braking device 104.

Further, based on the information on the presence/absence of slippage asobtained from the slippage determining circuit 210, the control device211 effects normal operation of the elevator when there is no slippagebetween the governor rope 203 and the governor sheave 201, and outputsthe actuation signal to the hoisting machine braking device 104 whenslippage occurs.

The hoisting machine braking device 104 and the safety device 33 areeach actuated upon the inputting of the actuation signal.

It should be noted that a processing device 214 includes the first speeddetecting portion 208, the second car speed calculating circuit 209, andthe slippage determining circuit 210. Further, an elevator rope slippagedetecting device 215 includes the encoder 204, the car speed sensor 205,and the processing device 214. Otherwise, this embodiment is of the sameconstruction as Embodiment 11.

Next, operation will be described. When a rotational position signalfrom the encoder 204 is inputted to the car position calculating circuit212, the position of the car 3 is obtained by the car positioncalculating circuit 212. Thereafter, information on the position of thecar 3 is outputted from the car position calculating circuit 212 to thecontrol device 211 and to the first car speed calculating circuit 213.Then, the first car speed calculating circuit 213 obtains the speed ofthe car 3 based on the information on the position of the car 3.Thereafter, information on the speed of the car thus obtained by thefirst car speed calculating circuit 213 is outputted to the controldevice 211 and to the slippage determining circuit 210.

Further, the second car speed calculating circuit 209 is inputted withinformation on the difference in frequency as measured by the car speedsensor 205. Accordingly, the speed of the car 3 is obtained by thesecond car speed calculating circuit 209. Thereafter, information on thespeed of the car 3 as obtained by the second car speed calculatingcircuit 209 is outputted to the slippage determining circuit 210.

The slippage determining circuit 210 detects the presence/absence ofslippage between the governor sheave 201 and he governor rope 203 on thebasis of the information on the speed of the car 3 from the first carspeed calculating circuit 213 and the information on the speed of thecar 3 from the second car speed calculating circuit 209. That is, theslippage determining circuit 210 determines that there is slippage whenthe difference between the speeds of the car 3 as respectively obtainedfrom the first and second car speed calculating circuits 213, 209 isequal to or larger than the reference value, and determines that thereis no slippage when the difference is smaller than the reference value.The information on the presence/absence of slippage is outputted fromthe slippage determining circuit 210 to the control device 211.

Thereafter, the operation of the elevator is controlled by the controldevice 211 on the basis of the information on the position of the car 3from the car position calculating circuit 212, the information on thespeed of the car 3 from the first car speed calculating circuit 213, andthe information on the presence/absence of slippage from the slippagedetermining circuit 210.

That is, when the speed of the car 3 is substantially the same in valueas the normal speed detection pattern 115 (FIG. 19), and the informationfrom the slippage determining circuit 210 indicates no slippage, theoperation of the elevator is set to normal operation by the controldevice 211.

For example, when, due to some cause, the speed of the car 3 increasesabnormally and exceeds the first abnormal speed 116 (FIG. 19), anactuation signal and a stop signal are outputted to the hoisting machinebraking device 106 (FIG. 18) and to the hoisting machine 101 (FIG. 18),respectively, from the control device 211. As a result, the hoistingmachine 101 is stopped, and the hoisting machine braking device 106 isactuated, thereby braking the rotation of the driving sheave 104.

When, after the actuation of the hoisting machine braking device 106,the speed of the car 3 further increases and exceeds the second abnormalspeed detection pattern 117 (FIG. 19), the control device 211 outputs anactuation signal to the safety device 33 (FIG. 18) while continuing tooutput the actuation signal to the hoisting machine braking device 106.As a result, the safety device 33 is actuated, thereby braking the car 3through the same operation as that of Embodiment 2.

Further, when, for example, slippage has occurred between the governorsheave 201 and the governor rope 203 due to some cause and thus theslippage determining circuit 210 determines that there is slippage, anabnormality signal indicating the occurrence of slippage is outputtedfrom the slippage determining circuit 210 to the control device 211.When the abnormality signal is inputted to the control device 211, anactuation signal and a stop signal are outputted to the hoisting machinebraking device 106 and the hoisting machine 101, respectively, from thecontrol device 211. As a result, the hoisting machine 101 is stopped,and the hosting machine braking device 106 is actuated, thereby bringingthe car 3 to an emergency stop.

In the elevator rope slippage detecting device 215 as described above,the slippage determining circuit 210 determines the presence/absence ofslippage between the governor sheave 201 and the governor rope 203through comparison between the speed of the car 3 obtained based on therotation of the governor sheave 201 and the speed of the car 3 obtainedthrough direct measurement, thereby making it possible to detect thepresence/absence of slippage between the governor sheave 201 and thegovernor rope 203 by means of a simple construction. Therefore, wheninformation on the position of the car 3 as obtained by measuring therotation of the governor sheave 201 is used for controlling theoperation of the elevator, it is possible to prevent a large deviationfrom occurring between the information on the position of the car 3 asrecognized by the control device 211 and the actual position of the car3, whereby the operation of the elevator can be controlled with enhancedaccuracy.

Further, as described above, the control on the operation of theelevator can be performed with enhanced accuracy by detecting thepresence/absence of slippage between the governor sheave 201 and thegovernor rope 203. Accordingly, the first and second abnormal speeddetection patterns 116, 117 (FIG. 19) each indicating an abnormality inthe speed of the car 3 can be set in the control device 211 so as tobecome progressively smaller toward the terminal end portions (the upperend portion and the lower end portion) of the hoistway 1, thereby makingit possible, for example, to significantly lower the maximum speed ofthe car 3 at the lower end portion of the hoistway 1 in the event of anabnormality. As a result, it is possible to reduce the size of a bufferfor absorbing the speed of the car 3 or the buffer space required forpreventing the collision of the car 3 with the lower end portion of thehoistway 1.

Further, the car speed sensor 205 used, which is provided at the lowerend portion of the car 3, is a Doppler sensor for obtaining the speed ofthe car 3 by measuring the difference between the respective frequenciesof the oscillating and reflected waves, so the speed of the car 3 can bedirectly measured by means of a simple construction, therebyfacilitating the detection of the speed of the car 3.

Further, in the elevator apparatus as described above, the operation ofthe elevator is controlled by the control device 211 on the basis of theinformation on the presence/absence of slippage as determined by theslippage determining circuit 210, so it is possible to prevent a largedeviation from occurring between the information on the position of thecar 3 as recognized by the control device 211 and the actual position ofthe car 3, whereby the control on the operation of the elevator can beperformed with enhanced accuracy. As a result, the requisite size of thebuffer or buffer space can be reduced, thereby making it possible toreduce the vertical length of the hoistway 1.

While in the above-described example the reflector 207 is provided atthe lower end portion of the hoistway 1 and the car speed sensor 205 isprovided at the lower end portion of the car 3 to thereby obtain therelative speed between the lower end portion of the hoistway 1 and thecar 3, it is also possible to provide the car speed sensor 205 at anupper end portion of the car 3 and to provide the reflector 207 at anupper end portion of the hoistway 1 to thereby obtain the relative speedbetween the upper end portion of the hoistway 1 and the car 3.Furthermore, it is also possible to provide the reflector 207 at each ofthe upper and lower end portions of the hoistway 1 and to provide thecar speed sensor at each of the upper and lower end portions of the car3 to thereby obtain the relative speed between the car 3 and each of theupper and lower end portions of the hoistway 1.

Further, while in the above-described example the reflecting surface 206for reflecting the oscillating wave is formed in the reflector 207, thewall surface (the bottom surface or the top surface) of the hoistway 1may serve as the reflecting surface.

Embodiment 18

FIG. 32 is a schematic diagram showing an elevator apparatus accordingto Embodiment 18 of the present invention. In this example, provided bythe side of the car 3 is a reflecting rail 222 provided with areflecting surface 221 extending along the travel direction of the car3. The reflecting rail 222 is fixed to a side wall surface of thehoistway 1.

The car speed sensor 205 used is the same Doppler sensor as that ofEmbodiment 17. Further, the car speed sensor 205 is provided at a lowerend portion of the car 3. Further, the car speed sensor 205 is adaptedto irradiate an oscillating wave toward the reflecting surface 221 andto receive the oscillating wave reflected by the reflecting surface 221as a reflected wave. The oscillating wave is irradiated in an obliquedirection with respect to the travel direction of the car 3. Otherwise,the construction and operation of Embodiment 18 are the same as those ofEmbodiment 17.

In the elevator rope slippage detecting device 215 as described above,the reflecting surface 221 formed in the reflecting rail 222 is providedby the side of the car 3 and extends along the travel direction of thecar 3, so the distance between the reflecting surface 221 and the carspeed sensor 205 becomes constant. Accordingly, it is possible to reducea detection error in detecting the speed of the car 3 by the car speedsensor 205, whereby the speed of the car 3 can be detected in a morestable manner.

While in the above-described example the car speed sensor 205 isprovided at the lower end portion of the car 3, the car speed sensor 205may be provided at an upper end portion of the car 3. Further, the carspeed sensor 205 may be provided in a side portion of the car 3 so as tobe opposed to the reflecting surface 221.

Further, while in the above-described example the reflecting surface 221is formed in the reflecting rail 222, the side wall surface of thehoistway 1 may serve as the reflecting surface.

Embodiment 19

FIG. 33 is a schematic diagram showing an elevator apparatus accordingto Embodiment 19 of the present invention. In this example, in theconstruction of Embodiment 17, the car speed sensor 205 is replaced withthe reflector 207, and the reflector 207 is replaced with the car speedsensor 205. That is, the car speed sensor 205 is provided at a lower endportion of the hoistway 1, and the reflector 207 is provided at a lowerend portion of the car 3. Otherwise, the construction and operation ofEmbodiment 19 are the same as those of Embodiment 17.

The elevator rope slippage detecting device 215 as described above alsoprovides the same effect as that of Embodiment 17. Further, the carspeed sensor 205 is provided at the lower end portion of the hoistway 1which is stably secured in place, so that the connecting structure, suchas electrical connection, for connecting the car speed sensor 205 to thecontrol panel 102 can be simplified. This facilitates the electricalconnection between the car speed sensor 205 and the control panel 102.

While in the above-described example the reflector 207 is provided atthe lower end portion of the car 3 and the car speed sensor 205 isprovided at the lower end portion of the hoistway 1 to thereby obtainthe relative speed between the lower end portion of the hoistway 1 andthe car 3, it is also possible to provide the reflector 207 at an upperend portion of the car 3 and to provide the car speed sensor 205 at anupper end portion of the hoistway 1 to thereby obtain the relative speedbetween the upper end portion of the hoistway 1 and the car 3. Further,it is also possible to provide the car speed sensor 205 at each of theupper and lower end portions of the hoistway 1 and to provide thereflector 207 at each of the upper and lower end portions of the car 3to thereby obtain the relative speed between the car 3 and each of theupper and lower end portions of the hoistway 1.

Further, while in the above-described example the reflecting surface 206is formed in the reflector 207, a surface (upper surface or lowersurface) of the car 3 may serve as the reflecting surface.

Further, while in each of Embodiments 17, 19 the car speed sensor 205used is the Doppler sensor utilizing the phenomenon of the Dopplereffect of the oscillating wave, the car speed sensor 205 used may be adistance sensor for measuring the reciprocation time of an energy wavebetween the car speed sensor 205 and the reflecting surface 206. In thiscase, the energy wave used may be, for example, light, an electric wave,an acoustic wave, or the like. Further, in the second car speedcalculating circuit 209, the distance is obtained from the reciprocationtime of the energy wave, and then the speed of the car 3 is obtained bydifferentiation of the distance obtained. In this way as well, the carspeed of the car 3 can be easily detected by means of a simpleconstruction.

Further, while in each of Embodiments 17 through 19 the speed of the car3 is measured by the car speed sensor over the entire height of thehoistway 1, the speed of the car 3 may be measured by the car speedsensor only in the acceleration/deceleration section near the upper endportion or lower end portion of the hoistway 1. In this case, areference sensor for detecting the passage of the car 3 therethrough isprovided at the boundary position between the acceleration/decelerationsection and the constant speed section, with the car speed sensor beingactuated upon the detection of the car 3 by the reference sensor.

Further, while in each of Embodiments 17 through 19 the rope slippagedetecting device 215 is applied to the elevator apparatus according toEmbodiment 11, the rope slippage detecting device 215 may be applied tothe elevator apparatus according to each of Embodiments 1 through 10 and12 through 16. In this case, in order to enable rope slippage detectionby the rope slippage detecting device 215, there is provided, within thehoistway 1, the governor rope connected to the car 3, and the governorsheave around which the governor rope is wound. Further, the operationof the elevator is controlled by the control device as an output portionbased on information from the rope slippage detecting device 215.

Further, while in each of Embodiments 1 through 19 the safety deviceapplies braking with respect to an overspeed (movement) of the car inthe downward direction, the safety device may be mounted upside down tothe car to thereby apply braking with respect to an overspeed (movement)in the upward direction.

1. An elevator rope slippage detecting device for detectingpresence/absence of slippage between a rope that moves together with acar traveling in a hoistway, and a pulley around which the rope is woundand which is rotated through movement of the rope, comprising: a pulleysensor configured to generate a signal in accordance with rotation ofthe pulley; a car speed sensor configured to directly detect a speed ofthe car based on a frequency of an oscillating wave received from areflecting surface on a side wall surface of the hoistway; and aprocessing device including a first speed detecting portion configuredto obtain a speed of the car based on information from the pulleysensor, a second car speed detecting portion configured to obtain aspeed of the car based on information from the car speed sensor, and adetermination portion configured to determine the presence/absence ofslippage between the rope and the pulley by comparing the speed of thecar obtained by the first speed detecting portion and the speed of thecar obtained by the second speed detecting portion with each other. 2.An elevator rope slippage detecting device according to claim 1, whereinthe car speed sensor includes a Doppler sensor provided to the car andconfigured to obtain the speed of the car by measuring a differencebetween a frequency of an oscillating wave irradiated toward areflecting surface provided in the hoistway and a frequency of areflected wave of the oscillating wave as reflected by the reflectingsurface.
 3. An elevator rope slippage detecting device according toclaim 2, wherein the reflecting surface is provided by a side of the carand extends along a travel direction of the car.
 4. An elevatorapparatus comprising: a car that travels in a hoistway; a rope thatmoves in accordance with movement of the car; a pulley around which therope is wound, the pulley being rotated through the movement of therope; a pulley sensor configured to generate a signal in accordance withrotation of the pulley; a car speed sensor configured to directly detecta speed of the car based on a frequency of an oscillating wave receivedfrom a reflecting surface on a side wall surface of the hoistway; aprocessing device configured to detect absence/presence of slippagebetween the rope and the pulley by obtaining a speed of the car based oninformation from the pulley sensor and a speed of the car based oninformation from the car speed sensor and to compare the speeds of thecar with each other; and a control device configured to controloperation of an elevator based on information from the processingdevice.